ISSF TU NA STOCK STATUS UPDATE - 2015 - Rio...

ISSF Status of Tuna Stocks – 2015 1

I S S F T UNA S T OCK ST AT US UPD A TE - 2 0 1 5 Status of the World Fisheries for Tuna

ISSF Technical Report 2015-03A

November, 2015

Suggested citation:

ISSF. 2015. ISSF Tuna Stock Status Update, 2015: Status of the world fisheries for tuna. ISSF Technical Report 2015-03A. International Seafood Sustainability Foundation, Washington, D.C., USA.


T A BL E OF CONT E NT S Executive Summary 3 Introduction 6

Purpose ........................................................................................................................................................................................................................... 6 Major commercial tunas ........................................................................................................................................................................................... 7 Global summary of catches.................................................................................................................................................................................... 12 Ratings methodology ................................................................................................................................................................................................ 13 Additional resources.................................................................................................................................................................................................. 14

Stocks in the Eastern Pacific Ocean 15 EPO Bigeye Tuna ....................................................................................................................................................................................................... 16 EPO Yellowfin Tuna .................................................................................................................................................................................................. 19 EPO Skipjack Tuna ................................................................................................................................................................................................... 22

Stocks in the Western and Central Pacific Ocean 24 WCPO Bigeye Tuna .................................................................................................................................................................................................. 25 WCPO Yellowfin Tuna ............................................................................................................................................................................................. 29 WCPO Skipjack Tuna .............................................................................................................................................................................................. 33

Pacific-wide Stocks 37 PO North Pacific Albacore ...................................................................................................................................................................................... 38 PO South Pacific Albacore ...................................................................................................................................................................................... 41 PO Pacific Bluefin Tuna ........................................................................................................................................................................................... 44

Stocks in the Atlantic Ocean 47 AO Bigeye Tuna ......................................................................................................................................................................................................... 48 AO Yellowfin Tuna .................................................................................................................................................................................................... 51 AO Eastern Skipjack Tuna ..................................................................................................................................................................................... 54 AO Western Skipjack Tuna ................................................................................................................................................................................... 56 AO Northern Albacore Tuna ................................................................................................................................................................................. 59 AO Southern Albacore Tuna .................................................................................................................................................................................. 62 AO Mediterranean Albacore Tuna ...................................................................................................................................................................... 65 AO Eastern Atlantic and Mediterranean Bluefin Tuna ................................................................................................................................. 67 AO Western Atlantic Bluefin Tuna ...................................................................................................................................................................... 70

Stocks in the Indian Ocean 73 IO Bigeye Tuna........................................................................................................................................................................................................... 74 IO Yellowfin Tuna ...................................................................................................................................................................................................... 77 IO Skipjack Tuna ....................................................................................................................................................................................................... 80 IO Albacore Tuna ...................................................................................................................................................................................................... 82

Southern Hemisphere Stocks 84 SH Southern Bluefin Tuna ..................................................................................................................................................................................... 84

Bibliography 87 Glossary and acronyms 89 Appendix 1. Bycatch 91

Impacts by gear type ............................................................................................................................................................................................... 91 RFMO bycatch mitigation and monitoring ........................................................................................................................................................ 92

Appendix 2. Version Log 95


E XE CUT IV E S UMMA RY There are 23 stocks of the major commercial tuna species worldwide (6 albacore, 4 bigeye, 4 bluefin, 5 skipjack and 4 yellowfin stocks). This document summarizes the results of the most recent scientific as-sessments of these stocks, as well as the current management measures adopted by the RFMOs. In addi-tion, this report ranks the status and management of the 23 stocks using a consistent methodology in terms of three factors: Abundance, Exploitation/Management (fishing mortality) and Environmental Im-pact (bycatch).

In 2013, the catch of major commercial tunas was 4.6 million tonnes. Fifty-eight percent of it was skipjack tuna, followed by yellowfin (27%), bigeye (9%) and albacore (6%). Bluefin tuna accounts for only 1% of the global catch.

Globally, 52% of the stocks are at a healthy level of abundance, 35% are overfished and 13% are at an intermediate level. In terms of exploitation, 52% of the stocks are experiencing a low fishing mortality rate, 13% are experiencing overfishing, and 35% have a high fishing mortality that is being managed ade-quately (Figure 1).

When viewed from the point of view of total catch (Figure 2), 87% of the catch comes from healthy stocks. This is due to the fact that skipjack stocks contribute more than one half of the global catch of tunas, and they are all in a healthy situation (Table 1). In contrast, most bluefin stocks and 2 out of 6 albacore stocks are overfished, but combined they make a relatively small fraction of the total catch.

Figure 1. Distribution of stocks of major commercial tunas according to abundance ratings (left) and fishing mortality ratings

(right). The percentages correspond to the number of stocks with a given ranking.

Figure 2. Distribution of stocks of major commercial tunas according to abundance ratings (left) and fishing mortality ratings (right). The percentages correspond to the total catch of all stocks with a given ranking.

52%35%

13%

52%

13%

35%

72%

23%

5%

87%

6%7%


Table 1. Biomass, Fishing Mortality (F) and Environmental Impact ratings for 23 tuna stocks. The table is sorted by species. Catch is for 2014 in thousands of tonnes. Catch for IO and Southern Hemisphere stocks (SBT) is for 2013.

STOC K CATCH B IOM AS S F BY CAT CH

Albacore tuna PO-ALB-N 91 PO-ALB-S 83 AO-ALB-N 27 AO-ALB-S 14 AO-ALB-M 2 IO-ALB 38 Bigeye tuna

EPO-BET 95 WPO-BET 155 AO-BET 73 IO-BET 109 Bluefin tuna

PO-PBF 17 AO-BFT-E 13 AO-BFT-W 2 SH-SBT 12 Skipjack tuna

EPO-SKJ 262 WPO-SKJ 1948 AO-SKJ-E 206 AO-SKJ-W 26 IO-SKJ 425 Yellowfin tuna

EPO-YFT 233 WPO-YFT 607 AO-YFT 103 IO-YFT 402


Table 2. Biomass, Fishing Mortality (F) and Environmental Impact ratings for 23 tuna stocks. The table is sorted by ocean or ocean region. Catch is for 2014 in thousands of tonnes. Catch for IO and Southern Hemisphere stocks (SBT) is for 2013.

STOC K CATCH B IOM AS S F BY CAT CH

Eastern Pacific

EPO-BET 95 EPO-YFT 233 EPO-SKJ 262 Western Pacific

WPO-BET 155 WPO-YFT 607 WPO-SKJ 1948 Pacific Ocean

PO-ALB-N 91 PO-ALB-S 83 PO-PBF 17 Atlantic Ocean

AO-BET 73 AO-YFT 103 AO-SKJ-E 206 AO-SKJ-W 26 AO-ALB-N 27 AO-ALB-S 14 AO-ALB-M 2 AO-BFT-E 13 AO-BFT-W 2 Indian Ocean

IO-BET 109 IO-YFT 402 IO-SKJ 425 IO-ALB 38 Southern Hemisphere

SH-SBT 12


I NTR OD UCT I ON

Purpose There are 23 stocks of the major commercial tuna species worldwide. These stocks are assessed and managed by five Tuna Regional Fishery Management Organizations (RFMOs). The purpose of this docu-ment is to summarize the status of the stocks according to the most recent scientific assessments, as well as the current management measures adopted by the RFMOs. Note that stock status can change between consecutive assessments because the stocks and fisheries are dynamic. In addition, the scientific bodies of the RFMOs sometimes make different model assumptions that can impact the interpretation of stock status, particularly in relation to MSY-based reference points. While this report does not replace the more detailed information available directly from the RFMOs, it does serve as a single source in which the information is presented uniformly.

The report is reviewed by the ISSF Scientific Advisory Committee, which provides advice on its content. The report does not advocate any particular seafood purchase decisions.

The report is organized by Ocean or by Ocean Region to try to match as closely as possible the man-dates of the different RFMOs.

Figure 3. Tuna RMFO Convention Areas. Top: International Commission for the Conservation of Atlantic Tunas

(ICCAT) and Indian Ocean Tuna Commission (IOTC). Bottom: Inter-American Tropical Tuna Commission (IATTC) and Western and Central Pacific Fisheries Commission (WCPFC)

Introduction

ISSF Status of Tuna Stocks - 2015 7

In addition, this report ranks the status and management of the 23 stocks using a consistent methodolo-gy (further explained below) in terms of three factors: Abundance, Exploitation/Management and Envi-ronmental Impact (bycatch).

This report is updated several times each year, usually after an RFMO assesses the stocks it is responsi-ble for, or adopts management recommendations. Appendix 2 provides a log of the updates.

Note that the IATTC and WCPFC Convention Areas have a region of overlap (Figure 3, bottom). In this report, catches of tropical tunas that occur in the overlap region are provided in the EPO summary. Similarly, the CCSBT Convention Area overlaps with those of ICCAT, IOTC and WCPFC. In this re-port, catches of southern bluefin tuna are provided in the Southern Hemisphere summary.

Major commercial tunas Seven species of tunas are of major commercial importance on a global scale: Three species of bluefin tuna, albacore, bigeye, yellowfin and skipjack. Due to differences in their distributions and the different fisheries that exploit them, the species are classified as "temperate" or "tropical". The temperate tunas are the bluefins, plus albacore; they are found in waters as cold as 10°C, but can also be found in tropical waters. Skipjack and yellowfin are classified as tropical and are found in waters with temperatures great-er than 18° C (although they can dive in colder waters). Bigeye could be classified as intermediate, but is often treated as a tropical species in fishery statistics. Ages/sizes at maturity relate to those at which 50% of females are expected to be mature.

A L B A C O R E T U N A Albacore (Thunnus alalunga) is a temperate tuna species, widely distributed in temperate and tropical waters of all oceans. The main fisheries are in temperate waters. In the Atlantic, their geographic limits are from 45-50° N and 30-40° S, while in the Indian Ocean, their distribution ranges from 5° N to 40° S with adults occurring from 5° N to 25° S. There are six albacore stocks assessed and managed by the RFMOs: North Pacific Ocean, South Pacific Ocean, North Atlantic Ocean, South Atlantic Ocean, Medi-terranean Sea and Indian Ocean.

Albacore tuna. Courtesy of Fisheries and Aquaculture Department/Food and Agriculture Organization of the United Nations.

Albacore tend to travel in single species schools, without the level of mixing as seen in other species. Association with floating objects is not common, as seen with tropical tunas. Small albacore are caught by trolling at the surface in cool water outside the tropics, while larger fish are caught deeper and mainly at lower latitudes (subtropical) using longline gear. Most of the catch is used for producing “white meat” canned tuna.

Albacore is one of the smaller major commercial tuna species, reaching sizes intermediate between skip-jack and yellowfin.

Introduction


Albacore: Approximate characteristics.

S I Z E ( C M ) W E I G H T (K G ) A G E (Y )

C O M M O N 40-100

M A X I M U M 130

M A T U R I T Y 75-90 8-15 2-5

B I G E Y E T U N A Bigeye (Thunnus obesus) are found in the subtropical and tropical areas of the Atlantic (but not in the Mediterranean), Indian and Pacific Oceans. Their geographical limits range from 55-60° N and 45-50° S. Juveniles and reproductively active adults are found in equatorial waters as well as at higher latitudes. Four stocks are assessed and managed by the RFMOs: Atlantic Ocean, Eastern Pacific, Western Pacific and Indian Ocean.

Bigeye tuna. Courtesy of Fisheries and Aquaculture Department/Food and Agriculture Organization of the United Nations.

Bigeye can form either free schools or those associated with floating objects. Juvenile bigeye will form schools with juvenile yellowfin and skipjack tunas. Smaller bigeye are caught on the surface by a range of gears including handline, ringnet and purse seine and are used mainly for canning, while the majority of larger/older fish are caught by longline fisheries for the sashimi market.

Bigeye reach similar maximum sizes to that of yellowfin. Individuals as large as 150 cm are common in some fisheries. Bigeye tuna are highly fecund and can spawn year round over a wide area of the tropical and subtropical oceans, providing environmental conditions (such as water temperature) are suitable. As with many tropical tuna species, environmental conditions are believed to significantly influence recruit-ment levels over time.

Introduction


Bigeye: Approximate characteristics.


C O M M O N 40-180 1.4-130

M A X I M U M 230 210 15

M A T U R I T Y 102-135 25-57 3-4

B L U E F I N T U N A Bluefin tuna (Thunnus spp.) are a temperate water fish comprised of 3 species, North Atlantic bluefin (Thunnus thynnus thynnus), Pacific bluefin (Thunnus orientalis), and southern bluefin tuna (Thunnus maccoyii), with the widest geographical distribution of the tunas. There are four bluefin stocks assessed and man-aged by the RFMOs: Western Atlantic, Eastern Atlantic (including the Mediterranean), Pacific and Southern hemisphere.

Southern (top) and Atlantic (bottom) bluefin tunas. Courtesy of Fisheries and Aquaculture Department/Food and Agriculture

Organization of the United Nations.

Bluefin are the largest of the tunas. Atlantic bluefin can reach 3 m in length.

Introduction


Bluefin: Approximate characteristics (Atlantic bluefin).


C O M M O N 80-200

M A X I M U M 300 (BFT) 668 (BFT) 25+

M A T U R I T Y 110-190 30-120 4-14

S K I P J A C K T U N A Skipjack (Katsuwonus pelamis) are found mainly in the tropical areas of the Atlantic, Indian and Pacific Oceans. Their geographic limits are 55-60° N and 45-50° S, with the greatest abundance seen in equato-rial waters. Five stocks are assessed and managed by the RFMOs: Eastern Atlantic, Western Atlantic, Eastern Pacific, Western Pacific and Indian Ocean.

Skipjack tuna. Courtesy of Fisheries and Aquaculture Department/Food and Agriculture Organization of the United Nations.

Skipjack form both free schools and schools associated with floating objects. They are the principal spe-cies associated with FADs and are caught in conjunction with juvenile yellowfin and bigeye tunas.

Skipjack are caught mainly on the surface by purse seine and pole-and-line gear and are the primary spe-cies in canned tuna.

Skipjack are the smallest of the major commercial tuna species. Skipjack are also highly fecund and can spawn year round over a wide area of the tropical and subtropical waters. Environmental conditions are believed to significantly influence recruitment and can produce widely varying recruitment levels between years.

Skipjack: Approximate characteristics.


C O M M O N 40-80

M A X I M U M 108 33 6-10

M A T U R I T Y 43 1.6 1-1.5

Introduction


Y E L L O W F I N T U N A Yellowfin (Thunnus albacares) are found in the subtropical and tropical areas of the Atlantic, Indian and Pacific Oceans. Yellowfin’s geographic limits are from 45°-50° N and South, although in the Pacific they occur mainly from 20° N and South. Four stocks are assessed and managed by the RFMOs: Atlantic Ocean, Eastern Pacific, Western Pacific and Indian Ocean.

Yellowfin tuna. Courtesy of Fisheries and Aquaculture Department/Food and Agriculture Organization of the United Nations.

Yellowfin form both free and associated schools with adults generally forming schools of similarly sized individuals. The free-swimming schools tend to contain large individuals and are mono-specific. In the eastern Pacific, schools are often associated with dolphin pods, an association not common elsewhere.

Small yellowfin are caught on the surface by a range of gears including handline, ringnet, purse seine and pole/line gear and are used mainly for canning, while the majority of larger/older fish are caught by both purse seine and longline fisheries, with the longline catch often shipped fresh to overseas markets.

Yellowfin tuna reach intermediate sizes between albacore and bigeye. Individuals as large as 150 cm are common in some fisheries. Yellowfin are highly fecund and can spawn year round over a wide area of the tropical and subtropical oceans, providing environmental conditions (such as water temperature and forage availability) are suitable. As with many tropical tuna species, environmental conditions are believed to significantly influence recruitment levels over time.

Yellowfin: Approximate characteristics.


C O M M O N 40-170 1.2-100

M A X I M U M 205 194 8

M A T U R I T Y 85-108 12-26 2-3

Introduction


Global summary of catches The global catch of albacore, bigeye, bluefin, skipjack and yellowfin in 2013 was 4.7 million tonnes, a 0.5% increase from 2012. Catches increased steadily until the early 2000s and have stabilized since then (Fig-ure Global-1). This plateau is explained by a continuous increase in skipjack catches offset by declining catches of yellowfin and bigeye, followed by a tendency in catches of all species to remain stable since the mid-2000s. (Figure Global-2). Ranked by species (using the 2009-2013 average = 4,529,584 tonnes), the majority of the catch is skipjack (57%), followed by yellowfin (27%), bigeye (9%), albacore (6%) and bluefin (1%). In terms of fishing gear, 64% of the catch is made by purse seining, followed by longline (12%), pole-and-line (10%), gillnets (4%) and miscellaneous gears (10%).

Figure Global-1. Global trends in catch (tonnes) of major commercial tunas, by species (top) and gear (bottom), 1950-2013.

Introduction


Figure Global-2. Global trends in catch (tonnes) of major commercial tunas, 1950-2013.

Ratings methodology For each stock, ISSF applies simple color ratings (Green, Yellow, Orange) to each of three factors. The protocol used is as follows:

1. The Chair of the ISSF Scientific Advisory Committee drafts the text based on reports from the RFMOs and assigns ratings according to the decision table below.

2. Members of the Scientific Advisory Committee review the draft and may revise the ratings to make them more precautionary (but not less), based on their knowledge of the RFMO scientific commit-tees.

3. The Scientific Advisory Committee approves the final report with changes as in step 2, above.

Introduction


Color Ratings Decision Table

STOC K AB UND ANC E

Spawning Biomass is at or above BMSY.

Spawning Biomass is below BMSY but it has been stable or increasing*. Yellow is also used in the absence of a stock assessment.

Spawning Biomass is below BMSY and it has not been stable or increas-ing*.

F I SH ING MORTAL ITY

F is below FMSY.

F is above FMSY but there are adequate management measures expected to end overfishing.

F is above FMSY and there are no adequate management measures to end overfishing, or the measures in place are insufficient

ENV IRONM ENT Adverse population effects on bycatch species are not expected for a given fishing gear/fishing method.

Adverse population effects on bycatch species are expected for a given fishing gear/fishing method, but there are either management measures or research programs in place expected to mitigate these effects. In addition, there is adequate monitoring of bycatch.

Adverse population effects on bycatch species are expected for a given fishing gear/fishing method, and there are no management measures or research programs in place expected to mitigate these effects. In addi-tion, bycatch monitoring is inadequate.

* As determined by the ISSF Scientific Advisory Committee based on the results of the stock assessment. Generally, a stable or increasing trend has to be observed for more than two years.

Environmental ratings are specific to different fishing methods. Appendix 1 provides the default ratings for major gear types.

Additional resources ISSF produces other reports that are complementary to this one, and are published as part of the ISSF Technical Reports series (http://iss-foundation.org/resources/downloads/?category=124). Two such re-ports can be particularly useful in providing additional information:

"Stock Assessment 101: Current practice for tuna stocks" gives a simple introduction to concepts and terms such as F, FMSY, BMSY, Recruitment, etc., which are encountered numerous times in this report.

"Status of the world fisheries for tuna: Management of tuna stocks and fisheries" (updated annually) pro-vides additional information about the RFMOs: How they are structured, who are their members, how they obtain their scientific advice, how are decisions made, and what management measures they have adopted that are not strictly for tuna stock management or bycatch mitigation.

http://iss-foundation.org/resources/downloads/?category=124

EPO


S T OCKS I N T HE E AS T ER N PA CI F I C OCE A N RFMO: Inter-American Tropical Tuna Commission (IATTC). EPO stocks are assessed by the IATTC staff, who makes recommendations to the IATTC. The SAC can also make recommenda-tions to the IATTC.

Last Scientific Committee (IATTC SAC) meeting: May, 2015.

Last Commission meeting: July, 2015.

Tuna stocks managed by IATTC: EPO Yellowfin, EPO Bigeye, EPO Skipjack. Also, North Pacific Albacore, South Pacific Albacore and Pacific Bluefin (also managed by WCPFC; see Stocks in the Pacific Ocean)

Data sources: The main sources of information for this section are IATTC (2015), Aires da Silva and Maunder (2015), Minte-Vera et al. (2015) and Maunder (2015).

Last update: November, 2015.

About 13 percent of the world production of tuna is from the eastern Pacific Ocean (EPO). Catches of skipjack, yellowfin and bigeye in 2014 were 589,700 tonnes, a 1% decrease from 2013. There has been a general decline in the total catch since 2003, which recorded the peak catch of 800,000 tonnes of these three species (Figure EPO-1).

Catches of albacore and Pacific bluefin also occur in the EPO. These stocks are also distributed in the western Pacific and are covered in a different section of this report, under Pacific Ocean.

Figure EPO-1. Trends in catch (mt) of bigeye, skipjack and yellowfin in the EPO region, by species (left) and gear (right),

1950-2014.

Average catches for the five-year period 2010-2014 (571,400 tonnes) provide an indication of the recent performance of the fisheries (Figure EPO.2): Skipjack accounts for 43% of the catches in weight, followed by yellowfin (40%) and bigeye (16%). Purse-seine vessels take 87% of the total catch, followed by longline (10%).

Figure EPO-2. Average 2010-2014 catches of skipjack, yellowfin and bigeye tuna in the EPO. The graph on the left shows

the percentages by species, and the graph on the right shows the percentages by gear type.

EPO-BET


EPO Bigeye Tuna Bigeye catches in 2014 were about 94,800 tonnes, a 14% increase from 2013. Longline fishing dominated the catches in weight until the mid-1990s. Purse seine fishing accounts for the majority of catches in re-cent years (62%), and longlining accounts for 38% (Figure EPO-3). Bigeye catches in the EPO by other gears are very minor.

Figure EPO-3. Catches of bigeye tuna in the EPO from 1954 to 2014, by gear type.

S T O C K A S S E S S M E N T In 2015, the IATTC conducted an updated assessment of the stock, using the same model as in the pre-vious full assessment conducted in 2013, which included several improvements in response to an exter-nal peer review. The results of this update indicate the following (EPO-4):

1. The current ratio of spawning biomass Bcurrent/BMSY is estimated at 1.06. This indicates that the stock is not in an overfished state. Between 2005 and 2010, there was an increasing trend in bi-omass, subsequent to IATTC management measures initiated in 2004. However, biomass has de-clined since 2010 and is now at its lowest historical level (19% of the unfished level).

2. The ratio of Fcurrent/FMSY is estimated at 0.87, indicating that overfishing was not occurring on av-erage in the most recent three years (2012-2014).

3. The estimate of MSY is 113,700 tonnes. MSY has been reduced to about half its level in 1993, when the expansion of the floating-object fishery began, as the overall selectivity from all fleets combined shifted towards smaller individuals. Since bigeye tuna can grow to be quite large (close to 200 cm), catching them when they are small results in a loss of potential yield, i.e. the catches that could be taken by other gears that target larger individuals, such as longlining. This is known as "growth overfishing".

4. As for all stock assessments that use MSY-based reference points, the assessment of stock status is highly sensitive to the assumed relationship between spawning biomass and recruitment (the base case assessment did not assume one). The results are more pessimistic if a stock-recruitment relationship is assumed (the stock would be assessed to be almost 30% below BMSY, and overfishing would be taking place F/FMSY = 1.23). The results are also more pessimistic if a higher value is assumed for the average size of the older fish, if lower rates of natural mortality are assumed for adult bigeye, and if the size data from longline fisheries are given higher weight in the analyses.

EPO-BET


The assessment estimated a strong increase in biomass between 2005 and 2010 in response to manage-ment measures, followed by a decline in biomass that could be driven by below-average recruitment levels, coinciding with La Niña events. Stock projections at the 2012-2014 average level of fishing mor-tality indicates that the spawning biomass will continue rebuilding and stabilize at an SBR of 0.25 around 2022, above the level corresponding to MSY (0.21). There is also concern with the excess fishing capaci-ty of the purse seine fleet in the EPO. For these reasons, and the sensitivity of the results to various assumptions, ISSF is taking a cautious view about the status of EPO bigeye.

Figure EPO-4. Temporal trend in the ratios Bcurrent/BMSY (x-axis) and Fcurrent/FMSY (y-axis) for bigeye tuna in the EPO. Dashed

lines represent interim limit reference points. The blue cross represents relative spawning biomass at the beginning of 2015 and relative fishing mortality for 2012-2014. Colors are taken from IATTC reports and do not necessarily correspond to the

colors used for ratings in the ISSF Stock Status Report.

M A N A G E M E N T Limit reference point: In 2014, on an interim basis, IATTC agreed to the staff's recommendation of the equilibrium spawning biomass corresponding to that which produces a 50% reduction in recruitment from the unfished level. This corresponds to a spawning biomass that is about 8% of the unfished level. The bigeye stock is above this limit.

Target reference point: In 2014, on an interim basis, IATTC agreed to the staff's recommendation of FMSY and BMSY. The bigeye stock is around this target.

Harvest control rule: In 2014, on an interim basis, IATTC agreed to the staff's recommendation of the rule that, if fishing mortality exceeds the level corresponding to MSY, it be reduced to that level.

The main conservation measure established by the IATTC for bigeye is Resolution C-13-01, which in-cludes an annual fishing closure for purse seine vessels greater than 182 tons carrying capacity. This measure calls for:

1. A 62-day closure for purse seiners greater than 182 tons capacity through 2016;

2. A seasonal closure of the purse seine fishery in an area known as "El Corralito", west of the Ga-lapagos Islands, where catch rates of small bigeye are high;

3. A full retention requirement for all purse seine vessels regarding bigeye, skipjack and yellowfin tunas;

4. Bigeye catch limits for the main longline fishing nations.

EPO-BET


S U M M A R Y

EPO BET Estimate Years Notes

Recent catch 95 2014

5-yr catch 93 2010-14

MSY 114 2012-14

F/FMSY 0.87

2012-14

B/BMSY 1.06 Start of 2015

TAC N/A

Catches and MSY in 1000 tonnes.

STOC K AB UND ANC E

B > BMSY. Spawning biomass is slightly above the MSY level.


F<FMSY. Although the point estimate of current F is below FMSY (so it could be rated Green), it is highly unlikely that increased fishing effort will result in significantly increased sustained catches, but it will signifi-cantly reduce spawning biomass.

ENV IRONM ENT 61% of the catch is made by purse seining on floating objects (including FADs). Several bycatch mitigation measures are in place (turtles, sharks, non-target species in general). There is 100% observer coverage on large purse seiners.

38% of the catch is made by longlining. Several mitigation measures are in place (sharks, turtles, sea birds). There will be 5% observer coverage on large longliners

Last date of a change in Color Ratings: November, 2015. Changes from the previous (August 2014) Color Ratings: The B rating changed from Orange to Green.

S T O C K

EPO-YFT


EPO Yellowfin Tuna Yellowfin catches in the EPO in 2014 were about 233,000 tonnes, a 2% increase from 2013. The main fishing gear is purse seine (96% of the catch), and recent catches by this gear are about 50% of the rec-ord high caught in 2002 (Figure EPO-5). Catches from longline vessels, although smaller in magnitude, have also declined substantially in recent years.

Figure EPO-5. Catches of yellowfin tuna in the EPO from 1950 to 2014, by gear type.

S T O C K A S S E S S M E N T The 2015 assessment used the same methodology as the previous one, with updated data. The assess-ment results indicated the following (Figure EPO-6):

1. The ratio of spawning biomass Bcurrent/BMSY is estimated to be 0.99, indicating that the stock is slightly overfished. The level of spawning biomass is estimated to have increased in recent years due to a decrease in the fishing mortality levels for middle-age yellowfin tuna since 2008.

2. The ratio Fcurrent/FMSY is estimated to be 0.86, indicating that overfishing is not occurring.

3. MSY is estimated to be 275,300 tonnes. Increasing the average weight of the yellowfin caught could increase the MSY.

4. The assessment of stock status is highly sensitive to the assumed relationship between spawning biomass and recruitment (the base case assessment did not assume one). The results are more pessimistic if a stock-recruitment relationship is assumed. The results are also sensitive to the natural mortality assumed for adult yellowfin and the length assumed for the oldest fish.

Analyses made using the base case assessment results indicate that increasing fishing mortality would change the long-term catches only marginally, while reducing the spawning biomass considerably. Be-cause of this, and taking into account the more pessimistic estimates of stock status obtained when a stock-recruitment relationship is assumed, ISSF believes that fishing mortality for yellowfin tuna in the EPO should not be allowed to increase.

EPO-YFT


Figure EPO-6. Temporal trend in the ratios Bcurrent/BMSY (x-axis) and Fcurrent/FMSY (y-axis) for yellowfin tuna in the EPO. Dashed lines represent interim limit reference points. The red dot represents relative spawning biomass in 2014 and relative fishing

mortality for 2012-2014. Colors are taken from IATTC reports and do not necessarily correspond to the colors used for ratings in the ISSF Stock Status Report.

M A N A G E M E N T Limit reference point: I In 2014, on an interim basis, IATTC agreed to the staff's recommendation of the equilibrium spawning biomass corresponding to that which produces a 50% reduction in recruitment from the unfished level. This corresponds to a spawning biomass that is about 8% of the unfished level. The yellowfin stock is above this limit,

Target reference point: In 2014, on an interim basis, IATTC agreed to the staff's recommendation of FMSY and BMSY. The yellowfin stock is around this target.

Harvest control rule: In 2014, IATTC agreed to the staff's recommendation of the rule that, if fishing mortality exceeds the level corresponding to MSY, it be reduced to that level.

The main conservation measure established by the IATTC for yellowfin is Resolution C-13-01, which includes an annual fishing closure for purse seine vessels greater than 182 tons carrying capacity. This measure calls for:



3. A full retention requirement for all purse seine vessels regarding bigeye, skipjack and yellowfin tunas.

EPO-YFT


S U M M A R Y

EPO YFT Estimate Years Notes


5-yr catch 230 2010-14

MSY 275 2012-14

F/FMSY 0.86

2012-14

B/BMSY 0.99 Start of 2015

TAC N/A


STOC K AB UND ANC E

B ≤ BMSY. Spawning biomass has been fluctuating below the MSY level and has increased in recent years.


F < FMSY. Although the point estimate of current F is below FMSY (so it could be rated Green), it is highly unlikely that increased fishing effort will result in significantly increased sustained catches, but it will signifi-cantly reduce spawning biomass.

ENV IRONM ENT 66% of the catch is made by purse seining on tuna-dolphin associations. Dolphin mortality is managed and closely monitored by AIDCP, with 100% observer coverage. However, the last dolphin surveys took place in 2006, and therefore the status of these populations is uncertain.

17% of the catch is made by purse seining on FADs. Several bycatch mitigation measures are in place (turtles, sharks, non-target species in general). There is 100% observer coverage on large purse seiners.

12% of the catch is made by purse seining on free schools of yellowfin.

4% of the catch is made by longlining. Several mitigation measures are in place (sharks, turtles, sea birds).

Last date of a change in Color Ratings: August, 2013. Changes from the previous (July 2012) Color Ratings: Biomass rating changed from Green to Yellow; gear impact for purse seine sets on tuna-dolphin associations changed from Green to Yellow.

EPO-SKJ


EPO Skipjack Tuna In 2014, skipjack catches were about 261,800 tonnes, a 7% decrease from 2013. Skipjack catches in the EPO are notoriously variable (Figure EPO-7). Purse seine fishing dominates the catches (over 99% of the total).

Figure EPO-7. Catches of skipjack tuna in the EPO from 1950 to 2014, by gear type.

S T O C K A S S E S S M E N T The last assessment for skipjack tuna was in 2012, based on four alternative types of analyses. In 2015 only one of the methods was updated to include data up to 2014. The analyses demonstrated a high de-gree of uncertainty, particularly with respect to the determination of MSY reference points and biomass levels. There may also be substantial differences between regions. The analyses of fishery indicators indi-cate that exploitation rates may be near the MSY level. However, there is no indication of a credible risk to the stock from overfishing.

M A N A G E M E N T Limit reference point: In 2014, on an interim basis, IATTC agreed to the staff's recommendation of the equilibrium spawning biomass corresponding to that which produces a 50% reduction in recruitment from the unfished level. This corresponds to a spawning biomass that is about 8% of the unfished level. Although no MSY-based reference points are available for EPO skipjack, it is very likely that the stock is above this limit.

Target reference point: In 2014, on an interim basis, IATTC agreed to the staff's recommendation of FMSY and BMSY. Although no MSY-based reference points are available for EPO skipjack, it is very likely that the stock is around this target.

Harvest control rule: In 2014, IATTC agreed to the staff's recommendation of the rule that, if fishing mortality exceeds the level corresponding to MSY, it be reduced to that level.

The main conservation measure established by the IATTC for skipjack is Resolution C-13-01, which in-cludes an annual fishing closure for purse seine vessels greater than 182 tons carrying capacity. This measure calls for:

EPO-SKJ




3. A full retention requirement for all purse seine vessels regarding bigeye, skipjack and yellowfin tunas;

S U M M A R Y

EPO SKJ Estimate Years Notes


5-yr catch 248 2010-14

MSY N/A

F/FMSY ≤1

B/BMSY ≥1

TAC N/A


STOC K AB UND ANC E

B > BMSY.


F ≤ FMSY.

ENV IRONM ENT 69% of the catch is made by purse seining on floating objects (including FADs). Several bycatch mitigation measures are in place (turtles, sharks, non-target species in general). There is 100% observer coverage on large purse seiners.

29% of the catch is made by purse seining on free schools of skipjack.

Last date of a change in Color Ratings: None. Changes from the previous (original) Color Ratings: None.

WCPO


S T OCKS I N T HE WE ST ER N A ND CENT R AL PA C I F I C OCE A N

RFMO: Western and Central Pacific Fisheries Commission (WCPFC). WCPO stocks are as-sessed by SPC and the results are reviewed by the SC which makes recommendations to the WCPFC.

Last Scientific Committee (SC) meeting: August, 2015.

Last Commission meeting: December, 2014.

Tuna stocks managed by WCPFC: WCPO Yellowfin, WCPO Bigeye, WCPO Skipjack. Also, North Pacific Albacore, South Pacific Albacore and Pacific Bluefin (also managed by IATTC; see Stocks in the Pacific Ocean). Note also that WCPFC and IATTC have an area of overlap; WCPO catch figures reported here do not include those WCPFC Convention Area catches made in the overlap area.

Data sources: The main sources of information for this section are WCPFC (2015), WCPFC (2015b), Harley et al. (2014), Davies et al. (2014) and Rice et al. (2014).


About 53 percent of the world production of tuna is from the western and central Pacific Ocean (WCPO). Provisional catches of skipjack, yellowfin, and bigeye in 2014 were 2,709,413 tonnes, a 7% in-crease from 2013. There has been a general increase in the total catch since 1980, with a small recess in 2010-2011 (Figure WCPO-1). This increase has been particularly pronounced for skipjack tuna.

Figure WCPO-1. Trends in catch (mt) of bigeye, skipjack and yellowfin in the WCPO region, by species (left) and gear (right),

1950-2014.

Average catches for the five-year period 2010-2014 (2,465,114 tonnes) provide an indication of the re-cent performance of the fisheries (Figure WCPO-2): Skipjack accounts for 71% of the catches in weight, followed by yellowfin (23%) and bigeye (6%). Purse-seine vessels take 74% of the total catch, followed by pole-and-line (9%), longline (6%), and other gears.

Figure WCPO-2. Average 2010-2014 catches of skipjack, yellowfin and bigeye tuna in the WCPO. The graph on the left

shows the percentages by species, and the graph on the right shows the percentages by gear type.

WCPO-BET


WCPO Bigeye Tuna Provisional bigeye catches in 2014 were about 154,600 tonnes, a 9% increase from 2013. The main fish-ing gears are purse seine (5-year average ~45%) and longline (45%) and (Figure WCPO-3). Bigeye catch-es in the WCPO by other gears are relatively minor.

Figure WCPO-3. Catches of bigeye tuna in the WCPO from 1950 to 2014, by gear type.

S T O C K A S S E S S M E N T In 2014, SPC conducted a new assessment in which data and methods changed substantially, following an extensive peer review process (Ianelli et al. 2012). Some of the main changes in the assessment included the following: increases in the number of spatial regions to better model the tagging and size data; inclu-sion of catch estimates from Vietnam and other fisheries previously missing; the use of operational long-line data for multiple fleets to better address the contraction of the Japanese fleet and general changes over time in targeting practices; improved modelling of recruitment; and a large amount of new tagging data corrected for differential post‐ release mortality and other tag losses. The new assessment indicat-ed the following (Figure WCPO-4):

1. The ratio of Fcurrent/FMSY is estimated at 1.57, indicating that overfishing is still occurring. In order to reduce fishing mortality to FMSY, a 36% reduction in fishing mortality is required from the av-erage 2008-2011 level. Projections made assuming the same fishing conditions as in 2012 into the future indicate that overfishing will continue.

2. The 2012 ratio of spawning biomass Bcurrent/BMSY in the base model is estimated at 0.77. This indi-cates that that the stock is in an overfished state.

3. The estimate of MSY is 108,500 tonnes. MSY has been reduced to less than half its levels prior to 1970 through harvest of small bigeye ("growth overfishing"). Recent catches (2009-2013 average = 142,532 tonnes) are substantially higher than MSY.

WCPO-BET


Figure WCPO-4. Temporal trend in the ratios Bcurrent/BMSY (x-axis) and Fcurrent/FMSY (y-axis) for bigeye tuna in the WCPO. The

purple dot represents the latest (2012) level. Colors are taken from WCPFC reports and do not necessarily correspond to the colors used for ratings in the ISSF Stock Status Report.

M A N A G E M E N T Limit reference point: 20% of the equilibrium spawning biomass that would be expected in the absence of fishing under current (most recent 10 years of the current assessment, excluding the last year) envi-ronmental conditions (20%SBcurrent, F=0). Adopted by the Commission in 2012. The bigeye breached this limit in 2012.

Target reference point: Not defined for the long term. Achieving F≤FMSY by 2017 implied as an interim target (CMM-2014-01). CMM-2014-06 calls for WCPFC to develop and implement a harvest strategy approach that includes target reference points, harvest control rules and other elements. At its 2015 meeting, the WCPFC is to establish a workplan for doing so.

Harvest control rule: Not defined. CMM-2014-06 calls for WCPFC to develop and implement a harvest strategy approach that includes target reference points, harvest control rules and other elements. At its 2015 meeting, the WCPFC is to establish a workplan for doing so.

The main binding conservation measure for bigeye established by the WCPFC is CMM 2014-01 that aims to reduce fishing mortality to F≤FMSY by the end of 2017. The measures call for the following in 2014-2017:

1. A 3-month closure (July through September) of fishing on FADs in EEZ waters and on the High Seas between 20°N and 20°S. VMS polling frequency is increased to 30 minutes during the clo-sure;

2. In 2015 and 2016, in addition to (1), each member shall choose between extending the FAD clo-sure for a total of 5 months (January, February, July, August and September), or limiting the number of FAD sets to be less than the number of sets made by its vessels in a reference period

WCPO-BET


specified in the CMM. In 2017, a prohibition on FAD sets on the high seas will apply, except for vessels purse seine flagged to Kiribati.

3. A limitation in the number of vessel days: For PNA members, the limit in their EEZs is the 2010 level. For other coastal states with effort in their EEZs exceeding 1,500 days annually over (2006-2010), the limit is either the 2001-2004 average or the 2010 level. For non-SIDS members, purse seine effort on the high seas will be limited to levels specified in the CMM.

4. Each member shall not allow the number of fishing days in the high seas to increase above limits specified in the CMM;

5. A requirement to submit FAD management plans, including information on strategies used to implement the closure and other measures for reducing small bigeye mortality;

6. A full-retention requirement for all purse seine vessels regarding bigeye, skipjack and yellowfin tunas between 20°N and 20°S;

7. 100% Regional observer coverage for all purse seine vessels fishing on the high seas, on the high seas and in waters under the jurisdiction of one or more coastal States, or vessels fishing in wa-ters under the jurisdiction of two or more coastal States during the same trip; all purse seiners fishing between 20N and 20S must have an observer onboard, unless they fish exclusively in their EEZ.

8. A limit between 20N and 20S in the number of purse seine and longline vessels with freezing ca-pacity at the current level for most countries (and specifically not including vessels of Small Island Developing States);

9. Flag-specific catch limits for bigeye caught by longliners, with monthly reporting to monitor the utilization of the limits;

In addition, CMM 2009-02 provides more guidance on the FAD closure and full retention requirements.

The first comprehensive management plan adopted for tropical tunas was CMM 2008-01. This measure was amended in CMM-2011-01 and replaced by CMM 2012-01, CMM-2013-01 and CMM-2014-01 in efforts by WCPFC members to reach a compromise and not allow the fisheries to go unmanaged. Overfishing of bigeye remains a major concern.

WCPO-BET


S U M M A R Y

WCPO BET Estimate Years Notes


5-yr catch 147 2010-14

MSY 109 2008-11

F/FMSY 1.57 2008-11

B/BMSY 0.77 2012

TAC N/A


STOC K AB UND ANC E

B < BMSY. The stock has been subjected to overfishing for over one decade, and is now overfished. Spawning biomass is below the Limit Reference Point adopted by WCPFC.


F > FMSY. The WCPFC management measures in place appear to be insufficient to end overfishing in the short term.

ENV IRONM ENT 45% of the catch is made by longlining. Several mitigation measures are in place (sharks, turtles, sea birds). Monitoring is deficient.

40% of the catch is made by purse seining on floating objects (including FADs). Several bycatch mitigation measures are in place (turtles, sharks). There is 100% observer coverage on part of the purse seine fleet.

5% of the catch is made with purse seining on free schools, with little impact on non-target species.

4% of the catch is made by pole-and-line fishing, with unknown impacts on baitfish stocks.

Last date of a change in Color Ratings: August, 2014. Changes from the previous (original) Color Ratings: Biomass rating changed from Green to Orange.

WCPO-YFT


WCPO Yellowfin Tuna Provisional yellowfin catches in the WCPO in 2014 were about 607,200 tonnes, an 11% increase from 2013. The main fishing gear is purse seine (62% of the catch). Eighteen percent of the catches are also taken by a number of mixed gears in the Philippines and Indonesia, and 16% by longliners (Figure WCPO-5).

Figure WCPO-5. Catches of yellowfin tuna in the WCPO from 1950 to 2014, by gear type.

S T O C K A S S E S S M E N T A new yellowfin assessment was conducted in 2014. The SPC made many improvements to the data and models, following some of the recommendations made during the peer review of the bigeye assessment. Some of the main changes in the assessment included the following: increases in the number of spatial regions to better model the tagging and size data; inclusion of catch estimates from Vietnam and other fisheries previously missing; the use of operational longline data for multiple fleets to better address the contraction of the Japanese fleet and general changes over time in targeting practices; improved model-ling of recruitment; and a large amount of new tagging data corrected for differential post‐ release mor-tality and other tag losses. The results were similar to those from the previous (2011) assessment and indicated that (Figure WCPO-6):

1. The yellowfin stock is not in an overfished state as spawning biomass (in 2012) is above the BMSY level (Bcurrent/BMSY = 1.24, range between 1.05 and 1.51 across different models).

2. The ratio Fcurrent/FMSY (for the period 2008-2011) is estimated to be 0.72 (range across different models between 0.58 and 0.90), indicating that overfishing is not occurring. However, the latest catches are close to or exceed MSY.

3. MSY is estimated to be 586,400 tonnes.

4. The optimistic estimate of overall stock status should be tempered by the patterns estimated at a sub-regional level. The tropical Pacific, from which most of the catches are taken, is at least ful-ly exploited with no potential for a substantial increase in catches to be sustainable.

WCPO-YFT


Figure WCPO-6. Temporal trend in the ratios Bcurrent/BMSY (x-axis) and Fcurrent/FMSY (y-axis) for yellowfin tuna in the WCPO,

1952-2012. The pink dot represents the latest (2012) situation. Colors are taken from WCPFC reports and do not neces-sarily correspond to the colors used for ratings in the ISSF Stock Status Report.

M A N A G E M E N T Limit reference point: 20% of the equilibrium spawning biomass that would be expected in the absence of fishing under current (most recent 10 years of the current assessment, excluding the last year) envi-ronmental conditions (20%SBcurrent, F=0). The yellowfin stock is estimated to be above this limit.

Target reference point: Not defined. CMM-2014-06 calls for WCPFC to develop and implement a har-vest strategy approach that includes target reference points, harvest control rules and other elements. At its 2015 meeting, the WCPFC is to establish a workplan for doing so.


The main binding conservation measure for yellowfin established by the WCPFC is CMM 2014-01. The measures call for the following in 2014-2017:


2. In 2015 and 2016, in addition to (1), each member shall choose between extending the FAD clo-sure for a total of 5 months (January, February, July, August and September), or limiting the number of FAD sets to be less than the number of sets made by its vessels in a reference period specified in the CMM. In 2017, a prohibition on FAD sets on the high seas will apply, except for vessels purse seine flagged to Kiribati.

3. A limitation in the number of vessel days: For PNA members, the limit in their EEZs is the 2010 level. For other coastal states with effort in their EEZs exceeding 1,500 days annually over (2006-

WCPO-YFT


2010), the limit is either the 2001-2004 average or the 2010 level. For non-SIDS members, purse seine effort on the high seas will be limited to levels specified in the CMM.


5. Each member shall not allow its catch of yellowfin to increase;




9. A limit between 20N and 20S in the number of purse seine and longline vessels with freezing ca-pacity at the current level for most countries;

In addition, CMM 2009-02 provides more guidance on the FAD closure and full retention requirements. CMM-2014-01 requires members to adopt measures so that their catch of yellowfin tuna does not in-crease.

WCPO-YFT


S U M M A R Y

WCPO YFT Estimate Years Notes


5-yr catch 561 2010-14

MSY 586 2008-11

F/FMSY 0.72 2008-11

B/BMSY 1.24 2012

TAC N/A


STOC K AB UND ANC E

B > BMSY.


F < FMSY. The overall estimate of current F is below FMSY, and therefore the rating could be Green. However, due to heavy fishing effort in the tropical region, there is little or no room for increased fishing pressure on the stock overall.

ENV IRONM ENT 30% of the catch is made by purse seining on floating objects (including FADs). Several bycatch mitigation measures are in place (turtles, sharks). There is 100% observer coverage on part of the purse seine fleet.


18% of the catch is made by other gears such as gillnets, with unknown impacts on non-target stocks.

16% of the catch is made by longlining. Several mitigation measures are in place (sharks, turtles, sea birds). Monitoring is deficient.


WCPO-SKJ


WCPO Skipjack Tuna The WCPO Skipjack stock supports the largest tuna fishery in the world, accounting for 38% of world-wide tuna landings. Catches in 2014 were 1,947,600 tonnes, a 6% increase from 2013. Purse seining, which accounts for 81% of the catches, increased steadily over the past three decades. In contrast, pole-and-line fishing (about 10%) has been declining steadily (Figure WCPO-7).

Figure WCPO-7. Catches of skipjack tuna in the WCPO from 1950 to 2014, by gear type.

S T O C K A S S E S S M E N T A new skipjack assessment was conducted in 2014. The SPC made many improvements to the data and models, following some of the recommendations made during the peer review of the bigeye assessment. Some of the main changes in the assessment included the following: increases in the number of spatial regions to better model the tagging and size data; improved modelling of recruitment; and a large amount of new tagging data corrected for differential post‐ release mortality and other tag losses. The new assessment indicated the following (Figure WCPO-8):

1. Fishing mortality rates tended to be higher during the last decade than for the preceding period. The ratio Fcurrent/FMSY is estimated to be 0.61, indicating that overfishing is not occurring.

2. The stock is not in an overfished state as spawning biomass (in 2012) is above the BMSY level (Bcurrent/BMSY = 1.74).

3. MSY is estimated to be 1.619 million tonnes. Recent catches slightly exceed MSY.

WCPO-SKJ


Figure WCPO-8. Temporal trend in the ratios Bcurrent/BMSY (x-axis) and Fcurrent/FMSY (y-axis) for skipjack tuna in the WCPO. The pink dot represents the 2012 level. Colors are taken from WCPFC reports and do not necessarily correspond to the colors

used for ratings in the ISSF Stock Status Report.

M A N A G E M E N T Limit reference point: 20% of the equilibrium spawning biomass that would be expected in the absence of fishing under current (most recent 10 years of the current assessment, excluding the last year) envi-ronmental conditions (20%SBcurrent, F=0). The skipjack stock is above the limit.

Target reference point: Not defined. However, TRPs of 40%, 50% and 60% of unfished spawning stock biomass are being considered for skipjack by WCPFC. Current levels of spawning biomass are within this range. CMM-2014-06 calls for WCPFC to develop and implement a harvest strategy approach that in-cludes target reference points, harvest control rules and other elements. At its 2015 meeting, the WCPFC is to establish a workplan for doing so.


The main binding conservation measure for skipjack established by the WCPFC is CMM 2014-01. The measures call for the following in 2014-2017:


2. In 2015 and 2016, in addition to (1), each member shall choose between extending the FAD clo-sure for a total of 5 months (January, February, July, August and September), or limiting the number of FAD sets to be less than the number of sets made by its vessels in a reference period

WCPO-SKJ


specified in the CMM. In 2017, a prohibition on FAD sets on the high seas will apply, except for vessels purse seine flagged to Kiribati.

3. A limitation in the number of vessel days: For PNA members, the limit in their EEZs is the 2010 level. For other coastal states with effort in their EEZs exceeding 1,500 days annually over (2006-2010), the limit is either the 2001-2004 average or the 2010 level. For non-SIDS members, purse seine effort on the high seas will be limited to levels specified in the CMM.





8. A limit between 20N and 20S in the number of purse seine and longline vessels with freezing ca-pacity at the current level for most countries.

In addition, CMM 2009-02 provides more guidance on the FAD closure and full retention requirements.

WCPO-SKJ


S U M M A R Y

WCPO SKJ Estimate Years Notes


5-yr catch 1757 2010-14

MSY 1619 2008-11

F/FMSY 0.61

2008-11

B/BMSY 1.74 2012

TAC N/A


STOC K AB UND ANC E

B > BMSY.


F ≤ FMSY.

ENV IRONM ENT 42% of the catch is made by purse seining on floating objects (including FADs). Several bycatch mitigation measures are in place (turtles, sharks).



9% of the catch is made by other gears such as gillnets, with unknown impacts on non-target stocks.


PO


PA C I F I C -WID E S T OCKS RFMOs: Western and Central Pacific Fisheries Commission (WCPFC) and Inter-American Trop-ical Tuna Commission (IATTC). The ISC evaluates North Pacific albacore and Pacific bluefin and the results are reviewed by the IATTC staff, the IATTC SAC and the WCPFC SC, who make recommendations to either IATTC or WCPFC. The SPC evaluates South Pacific albacore and the results are reviewed by the WCPFC SC. The SC makes recommendations to the WCPFC.

Last Scientific Committee meetings:

• WCPFC: August, 2015 • IATTC: May, 2015 • ISC: July 2015

Last Commission meeting:

• WCPFC: December, 2014 • IATTC: July, 2015

Three of the major commercial tunas with Pacific-wide distributions are warranted treatment as Pacific-wide stocks due to their scales of movement between the WCPO and the EPO: North Pacific albacore, South Pacific albacore and Pacific bluefin. The responsibility for their manage-ment is shared between IATTC and WCPFC.

Data sources: The main sources of information for this section are Harley et al. (2015), ISC (2014a), ISC (2014b), ISC (2015) and WCPFC (2015).


PO-ALB-N


PO North Pacific Albacore North Pacific albacore catches in 2014 were about 90,700 tonnes, a 3% decrease from 2013. The main fishing gears are longline (39%) and pole-and-line (35%), followed by trolling (24%) (Figure PO-3). Catch-es by longlining have shown a decreasing trend since 1997.

Figure PO-3. Catches of albacore tuna in the North PO from 1950 to 2014, by gear type.

S T O C K A S S E S S M E N T The north Pacific albacore stock was reassessed in 2014. The assessment results indicated that (Figure PO4):

1. The stock is not in an overfished state.

2. Fishing mortality is lower than many commonly-used reference points that are used as proxies for FMSY.

PO-ALB-N


Figure PO-4. Temporal trend in the ratios Bcurrent/Bref (x-axis) and Fcurrent/Fref (y-axis) for North Pacific albacore tuna. The plot is

illustrative as neither ISC or WCPFC or IATTC have adopted reference points for North Pacific albacore.

M A N A G E M E N T Limit reference point: Not defined.

Target reference point: Not defined.

Harvest control rule: Not defined.

The main binding conservation measure for North Pacific albacore established by the WCPFC is CMM 2005-03 which called for members not to increase fishing effort directed at North Albacore beyond the "current level". Similarly, in the IATTC, Resolution C-05-02 called for members not to increase fishing effort directed at North Albacore beyond the "current level". IATTC Resolution C-13-03 supplements C-05-02 and requires the reporting of fishing vessel information for 2007-2012.

PO-ALB-N


S U M M A R Y

PO ALB-N Estimate Years Notes


5-yr catch 85 2010-14

MSY N/A

F/FMSY 1<

B/BMSY >1

TAC N/A


STOC K AB UND ANC E

B > BMSY.


F ≤ FMSY. Although the point estimate of current F is below various FMSY proxies (so it could be rated Green), it is highly unlikely that in-creased fishing effort will result in significantly increased sustained catches, but it will significantly reduce spawning biomass. Both IATTC and WCPFC have measures in place to limit fishing effort or fishing capacity targeted on this stock.

ENV IRONM ENT 39% of the catch is made by longlining. Several bycatch mitigation measures are in place (turtles, sharks, sea birds).

35% of the catch is made by pole-and-line fishing, with unknown impacts on baitfish species.

24% of the catch is made by trolling, with little impact on non-target species.


PO-ALB-S


PO South Pacific Albacore South Pacific albacore extends beyond the WCPFC Convention Area. However, the stock is assessed by WCPFC for the area of the Pacific south of the Equator and between 140°E and 110°W. South Pacific albacore catches in 2014 were about 83,000 tonnes, a 2% decrease from 2013. The main fishing gear is longline, accounting for 96% of the catch. Relatively minor amounts are taken by other gears like trolling (Figure PO-5).

Figure PO-5. Catches of albacore tuna in the South PO from 1950 to 2014, by gear type.

S T O C K A S S E S S M E N T The last assessment was conducted by WCPFC in 2015 and covers only the WCPFC Convention Area South of the equator. Some other changes from the previous (2012) assessment were: having spatial structure in the model, new datasets (age-length and tagging data) and some changes to assumed biologi-cal parameters. The assessment results were similar to those in 2012 and indicated the following (Figure PO-6):

1. The estimated ratio Fcurrent/FMSY in 2009-2012 is 0.39, indicating that overfishing is not occurring. However, further increases in effort will yield little or no increase in long-term catches and re-sult in further reduced catches. SC11 reiterates the advice of SC10 recommending that longline fishing mortality be reduced to avoid further decline in the vulnerable biomass so that economi-cally viable catch rates can be maintained.

2. The estimated ratio of spawning biomass Bcurrent/BMSY in 2013 is 2.86. This indicates that the stock is not in an overfished state. However, the stock's biomass may be approaching an unprofitably low level.

3. The estimate of MSY is 76,800 tonnes (the median across a large number of plausible model runs).

4. For the first time SC considered an index of economic conditions in the south Pacific albacore fishery (Reid and Raubani, 2015). This index, which integrates fish prices, catch rates, and fishing prices, estimates a strong declining trend in economic conditions, reaching an historical low in

PO-ALB-S


2013. While there was a slight recovery in 2014, conditions are still well below the average pri-marily due to high fishing costs and continued low catch rates.

Figure PO-6. "Majuro plot" for albacore tuna in the South Pacific Ocean representing stock status in terms of spawning po-tential depletion and fishing mortality. The red zone represents spawning potential levels lower than the agreed limit refer-

ence point which is marked with the solid black line. The orange region is for fishing mortality greater than FMSY (FMSY is marked with the black dashed line).. The pink circle the latest period (2013). Colors are taken from WCPFC reports and do

not necessarily correspond to the colors used for ratings in the ISSF Stock Status Report.

M A N A G E M E N T Limit reference point: (WCPFC) 20% of the equilibrium spawning biomass that would be expected in the absence of fishing under current (most recent 10 years of the current assessment, excluding the last year) environmental conditions (20%SBcurrent, F=0).

Target reference point: Not defined. CMM-2014-06 calls for WCPFC to develop and implement a har-vest strategy approach that includes target reference points, harvest control rules and other elements. At its 2015 meeting, the WCPFC is to establish a workplan for doing so.


The main binding conservation measure for south Pacific albacore established by the WCPFC is CMM 2010-05 which aims to limit fishing mortality by establishing a cap on the number of vessels fishing for South Pacific albacore by each Commission member, with some exemptions for small island developing states. This capacity limitation is for the number of vessels not to increase over the 2005 level, or the 2001-2004 average.

PO-ALB-S


S U M M A R Y

PO ALB-S Estimate Years Notes


5-yr catch 82 2010-14

MSY 77 2013

F/FMSY 0.39

2009-2012

B/BMSY 2.86 2013

TAC N/A


STOC K AB UND ANC E

B > BMSY.


F < FMSY.

ENV IRONM ENT 96% of the catch is made by longlining. Several bycatch mitigation measures are in place (turtles, sharks, sea birds)

4% of the catch is made by trolling, with little impact on non-target species.


PO-PBF


PO Pacific Bluefin Tuna Reported Pacific bluefin catches in 2014 were about 17,100 tonnes, a 42% increase from estimates avail-able in 2013 (which had several gaps). Most of the catch (67%) occurs in the western Pacific. About 68% of the Pacific-wide catch is made by purse seine fisheries, followed by a variety of gears such as coastal set nets and troll (24%) and longline (8%). (Figure PO-7).

Figure PO-7. Catches of Pacific bluefin tuna from 1952 to 2014, by gear type.

S T O C K A S S E S S M E N T A full stock assessment was carried out by the ISC in 2014 (ISC, 2014b). The results corroborated the status information from the previous (2012) assessment (Figure PO-8):

1. The stock is heavily overfished, the biomass is near historically low levels and experiencing high explotation rates. The spawning stock biomass was 26,324 metric tonnes and slightly higher than the 2010 estimate. None the less, the spawning stock biomass has been declining for over ten years and in 2012 it was estimated to be less than 6% of the unfished level, and at or near the historically-lowest level.

2. Fishing mortality is estimated to be substantially higher than reference levels that are often used as proxies for FMSY (e.g., F in 2009-2011 is about 1.8 times greater than Fmax).

The Pacific bluefin catch is dominated by recruits (age 0) and juveniles (ages 1 to 3). Preliminary data indicate an unusually low catch of age-0 bluefin in 2012, while longline catch rates continue to decline. This may imply lower recruitment, which would adversely affect projected stock rebuilding and increase the risk of SB falling below its historical lowest level observed. In 2014, the ISC recommended further reductions in fishing mortality, especially for juvenile fish.

PO-PBF


Figure PO-8. Temporal trend in the ratios Bcurrent/Bref (x-axis) and Fcurrent/Fref (y-axis) for Pacific bluefin tuna. A. SSBMED and FMED;

B. SSB20% and SPR20%. Note that neither ISC or WCPFC or IATTC have adopted reference points for Pacific bluefin.


Target reference point: Not defined.

Harvest control rule: Not defined.

WCPFC CMM 2014-04 implements a multi-annual rebuilding plan commencing in 2015 to rebuild the Pacific bluefin spawning biomass to its median level (42,952 tonnes) by 2025 with at least 60% probability. It limits total fishing effort north of 20°N to below the average 2002-2004 levels. Members are also re-quired to reduce juvenile (less than 30 kg) catches below the 2002-2004 levels by at least 50%, with any overcatch deducted from the following years TAC. IATTC Resolution C-14-06 limits commercial catches to 6,600 tons in 2015 and 2016 combined.

PO-PBF


S U M M A R Y

PO-PBF Estimate Years Notes


5-yr catch 16 2010-14

MSY N/A

F/FMSY N/A F/Fmax = 1.8 for 2009-2011

B/BMSY N/A

TAC 5 2014 IATTC area


STOC K AB UND ANC E

B<BMSY was not estimated by ISC. However, B is 3.6% of the unfished level and at or near the historically-low level.


F relative to FMSY was not estimated by ISC. However, F is substantially higher than all proxies used as proxies for FMSY.

ENV IRONM ENT 68% of the catch is made by purse seining on free schools.

8% of the catch is made by longlining.

11% of the catch is made by trolling.

8% of the catch is made by set nets

Last date of a change in Color Ratings: August, 2013. Changes from the previous (original) Color Ratings: Biomass rating changed from Yellow to Orange.

AO


S T OCKS I N T HE AT L A NT I C OCE A N RFMO: International Commission for the Conservation of Atlantic Tunas (ICCAT). The stocks are assessed by the SCRS who makes recommendations to ICCAT.

Last Scientific Committee (SCRS) meeting: October, 2015

Last Commission meeting: November, 2014.

Tuna stocks managed by ICCAT: AO Yellowfin, AO Bigeye, Eastern AO Skipjack, Western AO skipjack, North AO Albacore, South AO Albacore, Mediterranean Albacore, Western AO blue-fin, Eastern AO bluefin.

Data sources: The main sources of information for this section ICCAT (2015).


About 10 percent of the world production of tuna is from Atlantic Ocean (AO) stocks. Catches of skip-jack, yellowfin, bigeye, albacore and bluefin in 2014 were 466,000 tons, a 3% decrease from 2013. There was a general tendency for the total catch to decline since the mid-1990s, followed by small increases since 2009 (Figure AO-1).

Figure AO-1. Trends in catch (mt) of bigeye, skipjack, yellowfin, albacore and bluefin in the AO region, by species (left) and

gear (right), 1950-2014.

Average catches for the five-year period 2010-2014 (478,400 tonnes) provide an indication of the recent performance of the fisheries (Figure AO.2): Skipjack accounts for 50% of the catches in weight, followed by yellowfin (22%), bigeye (16%), albacore (10%), and bluefin (3%). Purse-seine vessels take 59% of the total catch, followed by pole-and-line (some of which operate jointly with purse seiners, 19%), longline (16%) and other gears (6%).

Figure AO-2. Average 2010-2014 catches of skipjack, yellowfin, bigeye, albacore and bluefin tuna in the AO. The graph on

the left shows the percentages by species, and the graph on the right shows the percentages by gear type.

AO-BET


AO Bigeye Tuna Atlantic bigeye catches in 2014 were about 72,600 tonnes, a 7% increase from 2013. Catches by longline, the main fishing gear (49% of the catch), declined sharply between 1999 and 2006, but they have been stable during the last few years. Purse seine and pole-and-line vessels account for about 38% and 12% of the catches, respectively (Figure AO-3).

Figure AO-3. Catches of bigeye tuna in the AO from 1950 to 2014, by gear type.

S T O C K A S S E S S M E N T The last (2015) assessment conducted by SCRS (ICCAT Standing Committee on Research and Statistics) gave more pessimistic results overall than the 2010 assessment. The following conclusions were reached by SCRS, based on combining several model-data sets: (Figure AO-4):

1. The ratio of Fcurrent/FMSY in 2014 is estimated at 1.28, indicating that overfishing is occurring. Esti-mates of Fcurrent/FMSY from the model runs considered plausible ranged from 0.62 to 1.85.

2. The ratio of spawning biomass Bcurrent/BMSY in 2014 is estimated at 0.67. This indicates that that the stock is in an overfished state. Estimates of Bcurrent/BMSY from the model runs considered plausible ranged from 0.48 to 1.20.

3. The estimate of MSY is 78,800 tonnes (range: 67,700 to 85,000 tonnes). MSY has been reduced considerably through harvest of small bigeye. Current catches (72,600 tonnes) are below MSY.

AO-BET


Figure AO-4. Current Bcurrent/BMSY (x-axis) and Fcurrent/FMSY (y-axis) ratios for bigeye tuna in the AO. Colors are taken from

ICCAT reports and do not necessarily correspond to the colors used for ratings in the ISSF Stock Status Report.


Target reference point: Not defined. "Green" quadrant in Kobe plot implied as target (Rec. 11-13)

Harvest control rule: Not defined, but Rec. 11-13 provides a framework.

The main binding conservation measure established by ICCAT for bigeye is Recommendation 14-01, which amended several previous Recommendations. This 2012-2015 management plan calls for:

1. A Total Allowable Catch of 85,000 tonnes, with catch limits given to ICCAT members. The measure includes detailed provisions for countries to be penalized with lower quotas if their lim-its are exceeded;

2. A capacity limitation (country-specific) for the number of longline and purse seine vessels over 20 m in length;

3. The establishment of a record of vessels actively fishing for bigeye;

4. A two-month prohibition of fishing on floating objects in an area off West Africa, with 100% ob-server coverage during this time/area closure;

5. Annual submission of FAD management plans by countries with purse seine and baitboat (pole-and-line) fisheries;

While a TAC of 85,000 tonnes is specified, consistent with SCRS advice, the permissible catch under [14-01] exceeds 85,000 tonnes by a noticeable amount due to catch allowance made for CPCs not in-cluded in the allocation table. There is concern that fishing capacity remains high, and is probably growing due to longline and purse seine vessels moving from the IO into the AO due to piracy.

AO-BET


S U M M A R Y

AO BET Estimate Years Notes


5-yr catch 76 2010-14

MSY 79 2014 Range: 68-85

F/FMSY 1.28

2014 Range: 0.62-1.85

B/BMSY 0.67 2014 Range: 0.48-1.20

TAC 85 2012-2015


STOC K AB UND ANC E

B < BMSY.


F > FMSY.


30% of the catch is made by purse seining on floating objects (including FADs). Several bycatch mitigation measures are in place (turtles, sharks).

12% of the catch is made by pole-and-line fishing, with unknown impacts on baitfish stocks. Some of the baitboats in the Gulf of Guinea fish to-gether with the purse seiners, thus becoming like a single fleet.


Last date of a change in Color Ratings: November, 2015. Changes from the previous (original) Color Ratings: The Biomass rating changed from Green to Orange. The Fish-ing mortality rating changed from Yellow to Orange.

AO-YFT


AO Yellowfin Tuna Yellowfin catches in 2014 were about 103,400 tonnes, a 3% increase from 2013. The main fishing gear is purse seining (about 71% of the catch) (Figure AO-5). Purse seine catches have shown a general de-crease since the early 1990s, with two high peaks in 2001 and 2009. About 16% of the catch is made by longlining and 8% by pole-and-line vessels.

Figure AO-5. Catches of yellowfin tuna in the AO from 1950 to 2014, by gear type.

S T O C K A S S E S S M E N T The most recent full assessment of yellowfin tuna was carried out by SCRS in 2011. The SCRS advice is based on averaging the results from two types of models. These results are somewhat more pessimistic than those of the previous (2007) assessment and indicate that (Figure AO-6):

1. The (2010) ratio of Fcurrent/FMSY is estimated at 0.87 (range 0.68-1.40), indicating that overfishing is not occurring.

2. The (2010) ratio of spawning biomass Bcurrent/BMSY is estimated at 0.85 (range 0.61-1.12). This in-dicates that that the stock in 2006 is in an overfished state. However, the SCRS notes that the two types of models used show conflicting trends in the last few years: An increasing trend in bi-omass with one model, and a decreasing one with the other.

3. The estimate of MSY is 144,600 tonnes (range 114,200-155,100). MSY is lower than in previous decades because the overall fishery selectivity has shifted towards smaller yellowfin, mainly through fishing on FADs. Current catch (92,500 t) is below MSY.

AO-YFT


Figure AO-6. 2010 ratio of Bcurrent/BMSY (x-axis) and Fcurrent/FMSY (y-axis) for yellowfin tuna in the AO. The gray point is the

combined estimate from two types of models. The blue array of points reflects bootstrap estimates of uncertainty. Colors are taken from ICCAT reports and do not necessarily correspond to the colors used for ratings in the ISSF Stock Status Report.




The main binding conservation measure established by ICCAT for yellowfin is Recommendation 14-01, which amended several previous Recommendations. This 2012-2015 management plan calls for:

1. An overall TAC of 110,000 tonnes (unallocated by country);

2. The establishment of a record of vessels actively fishing for yellowfin;

3. A two-month prohibition of fishing on floating objects in an area off West Africa, with 100% ob-server coverage during this time/area closure;

4. Annual submission of FAD management plans by countries with purse seine and baitboat fisher-ies.

The TAC adopted by ICCAT is consistent with the advice provided by SCRS. While recent catches have been below the TAC, there is concern that fishing pressure on the stock could increase in the near fu-ture with the recent movement of purse seine and longline vessels from the IO into the AO due to pira-cy. This situation should be monitored closely.

AO-YFT


S U M M A R Y

AO YFT Estimate Years Notes


5-yr catch 105 2010-14

MSY 145 2010 Range: 131-147

F/FMSY 0.86

2010

B/BMSY 0.96 2010

TAC 110


STOC K AB UND ANC E

B < BMSY in 2010. Recent trends in spawning biomass are uncertain because the two assessment models used give conflicting results (one increasing and one declining).


F < FMSY. Although the point estimate of current F is below FMSY (and thus it could be rated Green), it is highly unlikely that increased fishing effort will result in significantly increased sustained catches, but it will significantly reduce spawning biomass.

ENV IRONM ENT 55% of the catch is made with purse seining on free schools, with little impact on non-target species




Last date of a change in Color Ratings: December, 2011. Changes from the previous (original) Color Ratings: The Biomass rating changed from Yellow to Orange.

AO-SKJ-E


AO Eastern Skipjack Tuna There are two (eastern and western) skipjack stocks in the Atlantic. Skipjack catches in the eastern At-lantic Ocean in 2014 were about 206,200 tonnes, a 7% decrease from 2013. Purse seine (81%) and pole-and-line (17%) dominate the catches (Figure AO-7). The purse seine catches had been decreasing from the early 1990s to 2009, but increased substantially since then; catches by other gears have remained stable.

Figure AO-7. Catches of skipjack tuna in the Eastern AO from 1950 to 2014, by gear type.

S T O C K A S S E S S M E N T The stock was assessed by SCRS in 2014, using data up to 2013. Regardless of the model used, the Committee was not in a position to provide a reliable estimate of the maximum sustainable yield and therefore nor provide quantitative advice on the state of the eastern stock. However, the SCRS con-cluded that:

1. The ratio of Fcurrent/FMSY is likely below 1.0, indicating that overfishing is not occurring.

2. The ratio of spawning biomass Bcurrent/BMSY is likely above 1.0, indicating that the stock is not in an overfished state.

3. The value of MSY is probably higher than previously estimated (143,000-170,000 tonnes).




The time-area closure established for bigeye and yellowfin through Recommendation 14-01 also affects this skipjack stock. SCRS has recommended that the catch and effort levels not exceed the level of catch in recent years

AO-SKJ-E


S U M M A R Y

AO SKJ-E Estimate Years Notes


5-yr catch 209 2010-14

MSY Probably higher than

prev. estimates (~157)

F/FMSY Likely <1

B/BMSY Likely >1

TAC N/A


STOC K AB UND ANC E

B > BMSY.


F < FMSY.

ENV IRONM ENT 74% of the catch is made by purse seining on floating objects (including FADs). Several bycatch mitigation measures are in place (turtles, sharks).




AO-SKJ-W


AO Western Skipjack Tuna There are two (eastern and western) skipjack stocks in the Atlantic. Skipjack catches in the western Atlantic Ocean in 2014 were about 26,300 tonnes, a 10% decrease from 2013. Pole-and-line fishing dom-inates the catches (91%), followed by purse seining (5%) (Figure AO-8). Pole and line catches have re-mained relatively stable (although highly variable) during the last two decades, while purse seine catches have declined.

Figure AO-8. Catches of skipjack tuna in the Western AO from 1950 to 2014, by gear type.

S T O C K A S S E S S M E N T The stock was assessed by SCRS in 2014, using data up to 2013. Different models were used, and the results were characterized by high uncertainty. The SCRS concluded that (Figure AO-9):

1. The ratio of Fcurrent/FMSY is around 0.7, indicating that overfishing is not occurring.

2. The ratio of spawning biomass Bcurrent/BMSY is close to 1.3, indicating that the stock is not in an overfished state.

3. The value of MSY is around 30,000-32,000 tonnes).

AO-SKJ-W


Figure AO-9. Temporal trend in the ratios Bcurrent/BMSY (x-axis) and Fcurrent/FMSY (y-axis) for skipjack tuna in the western AO. The

lines show the trends in the estimated biomass and fishing mortality ratios over time, using the ASPIC surplus production model. Colors are taken from ICCAT reports and do not necessarily correspond to the colors used for ratings in the ISSF

Stock Status Report.




ICCAT has not adopted conservation and management measures for this stock. SCRS has recommended that catches not be allowed to exceed MSY.

AO-SKJ-W


S U M M A R Y

AO SKJ-W Estimate Years Notes


5-yr catch 29 2010-14

MSY ~ 30-32 2013

F/FMSY ~ 0.7

B/BMSY ~ 1.3

TAC N/A


STOC K AB UND ANC E

B > BMSY.


F < FMSY.

ENV IRONM ENT 91% of the catch is made by pole-and-line fishing, with unknown impacts on baitfish stocks.



AO-ALB-N


AO Northern Albacore Tuna There are three stocks of albacore tuna in the ICCAT Area: North Atlantic, South Atlantic and Mediter-ranean. Albacore catches in the North Atlantic in 2014 were about 26,500 tonnes, an 8% increase from 2013. Catches are made by a variety of fishing gears including pole-and-line (28%), troll (25%), trawl (27%) and longline (18%) (Figure AO-10).

Figure AO-10. Catches of albacore tuna in the North AO from 1950 to 2014, by gear type.

S T O C K A S S E S S M E N T The most recent assessment for the northern stock of albacore was conducted by SCRS in 2013 using data up to 2011. The results indicate that (Figure AO-11):

1. The ratio of Fcurrent/FMSY is estimated at 0.72 (range 0.55-0.79), indicating that overfishing is not occurring.

2. The ratio of spawning biomass Bcurrent/BMSY is estimated at 0.94 (range 0.74-1.14). This indicates that that the stock is in an overfished state. However, most of the assessment model runs indicate that the stock has been increasing since the mid-1990s.

3. MSY is estimated at 31,700 tonnes. Current (2013) catch is 24,500 t. Catches have been below the MSY level since 2007.

AO-ALB-N


Figure AO-11. Temporal trend in the ratios Bcurrent/BMSY (x-axis) and Fcurrent/FMSY (y-axis) for albacore tuna in the northern AO. The line shows the trend in the estimated biomass and fishing mortality ratios over time. The solid circle marks the 2011

ratio value and the scattered points represent uncertainty around it. Colors are taken from ICCAT reports and do not neces-sarily correspond to the colors used for ratings in the ISSF Stock Status Report.

M A N A G E M E N T Limit reference point: Under development (Rec. 13-05).


Harvest control rule: Under development (Rec. 13-05). Rec. 11-13 provides a framework.

ICCAT Recommendation 98-08 limits the number of vessels targeting northern Atlantic albacore in each member country to the average level of 1993-1995.

Recommendation 13-05 established a Total Allowable TAC of 28,000 tonnes for 2014-2016, following the advice of the SCRS. However, permissible catch under [13-05] exceeds 28,000 tonnes due to catch allowance made for CPCs not included in the allocation table.

AO-ALB-N


S U M M A R Y

AO ALB-N Estimate Years Notes


5-yr catch 23 2010-14

MSY 32 2007

F/FMSY 0.72

2011 Range: 0.55-0.79

B/BMSY 0.94 2009-2011 Range: 0.74-1.14

TAC 28 2014-2016


STOC K AB UND ANC E

B < BMSY. Most of the model runs in the 2013 assessment suggest that the stock has been increasing in recent years. If catches are kept at the TAC level, the stock is expected to rebuild by 2019.


F < FMSY. There is a TAC to reduce fishing mortality that has been set following scientific advice to rebuild the stock.

ENV IRONM ENT 28% of the catch is made by pole-and-line fishing, with unknown impacts on baitfish stocks.

25% of the catch is made with trolling, with little impact on non-target species

27% of the catch is made with pelagic trawling, with some impact on non-target species. Monitoring of bycatch is poor.

18% of the catch is made by longlining. Several mitigation measures are in place (sharks, turtles). Monitoring is deficient.

Last date of a change in Color Ratings: December, 2013. Changes from the previous (original) Color Ratings: The Biomass rating changed from Orange to Yellow. The Fish-ing mortality rating changed from Yellow to Green.

AO-ALB-S


AO Southern Albacore Tuna There are three stocks of albacore tuna in the ICCAT Area: North Atlantic, South Atlantic and Mediter-ranean. Albacore catches in the South Atlantic in 2014 were about 13,700 tonnes (Figure AO-12), a 29% decrease from 2013. Catches are made primarily by longline (70%) and pole-and-line (26%)

Figure AO-12. Catches of albacore tuna in the South AO from 1950 to 2014, by gear type.

S T O C K A S S E S S M E N T The most recent assessment for the southern stock of albacore was conducted by SCRS in 2013. The assessment used similar models to the previous (2011) one. However, fewer input data series were used after screening of the available catch rate data. The overall analysis gave slightly more optimistic results than the previous assessment. The new analyses indicate that (Figure AO-13):

1. The median ratio of Fcurrent/FMSY in 2011 is estimated at 1.04 (range 0.38-1.32), indicating that overfishing is occurring.

2. The ratio of biomass Bcurrent/BMSY in 2012 estimated at 0.92 (range 0.71-1.26). This indi-cates that that the stock is in an overfished state.

3. MSY is estimated at 25,200 tonnes. Current (2013) catch is 19,200 t.

AO-ALB-S


Figure AO-13. Temporal trend in the ratios Bcurrent/BMSY (x-axis) and Fcurrent/FMSY (y-axis) for albacore tuna in the southern AO.

The eight panels are the trajectories from eight different models that were used in combination by the SCRS to produce advice. In each plot, the scatter of points represents uncertainty around the 2011 ratios. Colors are taken from ICCAT re-

ports and do not necessarily correspond to the colors used for ratings in the ISSF Stock Status Report.




Since 2011, following SCRS advice, the TAC was lowered to 24,000 tonnes (ICCAT Recommendations 11-05 and 13-06). However, permissible catch under the Rec. 13-06 exceeds 24,000 tonnes due to indi-vidual allocations. The Recommendation requires major fishing countries to improve their monitoring and reporting of catch.

AO-ALB-S


S U M M A R Y

AO ALB-S Estimate Years Notes


5-yr catch 20 2010-14

MSY 25 2011

F/FMSY 1.04

2011

B/BMSY 0.92 2012

TAC 24 2013-2016


STOC K AB UND ANC E

B < BMSY.


F ≈ FMSY. The overall TAC has been lowered to 24,000 t following scien-tific advice to allow the stock to rebuild. However, catches in 2011 and 2012 exceeded this level.



Last date of a change in Color Ratings: December, 2011. Changes from the previous (original) Color Ratings: The Biomass rating changed from Yellow to Orange. The Fish-ing mortality rating changed from Green to Yellow.

AO-ALB-M


AO Mediterranean Albacore Tuna There are three stocks of albacore tuna in the ICCAT Area: North Atlantic, South Atlantic and Mediter-ranean. Albacore catches in the Mediterranean in 2014 were about 2,400 tonnes, a 58% increase from 2013. Catches are highly variable and are made primarily by longline (77%) and the remainder by other surface gears (Figure AO-14).

Figure AO-14. Catches of albacore tuna in the Mediterranean Sea from 1950 to 2014, by gear type.

S T O C K A S S E S S M E N T The Mediterranean albacore stock was assessed for the first time in 2011. The data sets used are ex-tremely sparse and indices of abundance are generally lacking. In addition, there is considerable uncer-tainty with reported catches. The SCRS concluded that:

1. The ratio of Fcurrent/FMSY in 2010 is less than or equal to 1. Therefore, overfishing is probably not occurring.

2. The ratio of Bcurrent/BMSY cannot be estimated with the available data. Therefore it is not known if the stock is overfished.

3. The level of MSY cannot be estimated with the available data.




There are no conservation and management measures for Mediterranean albacore. The 2011 SCRS rec-ommended that the Commission adopt measures designed to limit increases in catch and fishing effort directed at Mediterranean albacore. However, the recent Commission meetings did not adopt any con-servation measures for the stock.

AO-ALB-M


S U M M A R Y

AO ALB-M Estimate Years Notes

Recent catch 2 2014

5-yr catch 3 2010-14

MSY N/A

F/FMSY ≤1

2009

B/BMSY N/A

TAC


STOC K AB UND ANC E

Unknown. Monitoring of basic fishery statistics is extremely poor and has made it impossible to estimate abundance in the stock assessment.


F≤FMSY. While the F level could be rated Green, there is so much uncer-tainty in the assessment results that a Yellow rating is given on a precautionary basis.

ENV IRONM ENT 77% of the catch is officially reported as made by longlining. Several mitigation measures are in place (sharks, turtles). Monitoring is very deficient.

23% of the catch is made by other surface gears, including gillnets. Monitoring is very deficient.

Last date of a change in Color Ratings: December, 2011. Changes from the previous (original) Color Ratings: The Fishing mortality rating changed from Orange to Yellow.

AO-BFT-E


AO Eastern Atlantic and Mediterranean Bluefin Tuna Atlantic bluefin tuna (Thunnus thynnus) are found in the entire North Atlantic and its adjacent seas, pri-marily the Mediterranean Sea. ICCAT recognizes two stocks: Western Atlantic, and eastern Atlantic and Mediterranean bluefin. There is considerable mixing between the two.

Eastern Atlantic bluefin catches have been subject to a high degree of mis-reporting between the mid-1990s and the recent past, although for the most recent few years, such mis-reported catch levels are thought to have diminished considerably. In 2014, reported catches were about 13,200 tonnes (Figure AO-15), a similar quantity as those reported in 2013. Purse seiners take 54% of the catch, followed by traps (22%), longline (16%), and a variety of surface gears, including pole-and-line, handline and trolling.

Figure AO-15. Catches of Eastern Atlantic and Mediterranean bluefin from 1950 to 2014, by gear type.

S T O C K A S S E S S M E N T In 2014, ICCAT’s SCRS conducted an update of the 2012 assessment of eastern Atlantic bluefin, applying the same methodologies and hypotheses adopted by the Committee in 2012 and catch, effort and size statistics through 2013. The stock assessment is subject to considerable uncertainties due to scarcity of CPUE data and to high levels of mis-reporting that took place primarily in the 2000s. The SCRS conclud-ed the following (Figure AO-16):

1. The current ratio of spawning biomass Bcurrent/BMSY (using F0.1 as a proxy for FMSY) is about 1.10 for the "medium recruitment" scenario, suggesting that the stock may not be in an overfished state. However, using other assumed levels of recruitment and mis-reporting in the past, the ratio of Bcurrent/BMSY ranges from 0.67 to 1.6.

2. The ratio of Fcurrent/FMSY (using the F0.1 proxy) is estimated at 0.36-0.40, depending on the assumed level of mis-reporting in the past. Thus, overfishing is not taking place. Catches have been reduced by over 70% since 2007 due to strict limits and controls.

3. The estimate of MSY is about 33,700-36,800 tonnes (ranges between 23,200 and 74,200 tonnes, depending on the assumed recruitment level). In Recommendation 14-04, ICCAT chose MSY to be the lowest value estimated by SCRS (23,256 tonnes).

AO-BFT-E


Figure AO-16. Current ratios Bcurrent/BMSY (x-axis) and Fcurrent/FMSY (y-axis) for eastern Atlantic bluefin tuna assuming inflated or reported catch (upper and lower panels) and considering low, medium and high recruitment levels (blue, green and red lines). Blue, green and red dots represent the distribution of the terminal year obtained through bootstrapping for the corresponding three recruitment levels. The left and right panels assume two different selectivity curves.The spread of symbols represents

uncertainty in the estimate of the current ratios.


Target reference point: Not defined for the long term. "Green" quadrant in Kobe plot implied as target (Rec. 11-13). Interim target is to achieve BMSY through 2022 with at least 60% probability (Rec. 14-04).


The eastern Atlantic and Mediterranean bluefin stock has been the subject of a rebuilding program since 2006 (ICCAT Rec. 06-05), which has been amended every year in 2007-2010 and again in 2012 (Rec. 12-03). The plan aims to rebuild the stock to BMSY by 2022 with at least 60% probability.

The rebuilding program (Rec. 14-04) is a very comprehensive management plan that combines multiple conservation elements with enforcement ones. The TACs for 2015 through 2017 are 16,142, 19,296 and 23,155 tonnes, respectively. In addition to the TACs, the plan includes the following measures, among others:

1. Manages fishing capacity (including mandated capacity adjustments to make fishing capacity more commensurate with quotas) and farming capacity;

2. Establishes closed fishing seasons for longliners (six months), purse seiners (11 months), and for pole and line, pelagic trawl and sport fishing vessels (eight months each);

3. Sets minimum sizes of 8 and 30 kg, depending on the fishery;

4. Establishes records of authorized fishing vessels and authorized farming facilities;

5. Requires weekly catch reports to national agencies and monthly catch reports to ICCAT;

AO-BFT-E


6. Establishes an observer program with 100% coverage for purse seiners and for transfers to cag-es;

7. Requires VMS on every vessel over 15 m in length, and transmissions of the VMS data to ICCAT;

8. Prohibits trade of bluefin not accompanied by valid catch documents (Rec. 09-01);

9. Establishes procedures for at-sea boarding and inspection;

10. Allows SCRS to access all MCS data from the management plan.

The multiple amendments made to the management plan since 2006 have resulted in increasingly tighter controls of the actual catches. Combined with lower quotas, fishing mortality rates have been reduced substantially (current F is below FMSY). Using the medium recruitment scenario, the SCRS estimates that the stock may have already rebuilt to BMSY, although considerable uncertainty remains. SCRS projections indicated that a gradual increase of the TAC up to the most conservative estimate of MSY would allow the stock to rebuild to BMSY even in the most pessimistic scenario. At its annual meeting in 2014, the Commission followed this advice.

S U M M A R Y

AO BFT-E Estimate Years Notes


5-yr catch 12 2010-14

MSY 23 2013 Range: 23-74

F/FMSY 0.4

2013

B/BMSY 1.10 2013 Range: 0.67 to 1.60

TAC 16, 19 and 23 2015-2017


STOC K AB UND ANC E

B > BMSY. Biomass is likely above BMSY. However, there still is considera-ble uncertainty with the assessment and one of the scenarios shows that B could be lower than the MSY level.


F < FMSY. Fishing mortality has clearly been reduced through a TAC and strict controls.

ENV IRONM ENT 54% of the catch is made by purse seiners that set on free schools.

16% of the catch is made by longlining. Several mitigation measures are in place.

22% of the catch is made by fixed traps that have minor impact on sensitive species.

3% of the catch is made by pole-and-line fisheries that have some impact on baitfish stocks.

Last date of a change in Color Ratings: February, 2015. Changes from the previous (original) Color Ratings: The Biomass rating changed from Orange to Yellow.

AO-BFT-W


AO Western Atlantic Bluefin Tuna Atlantic bluefin tuna are found in the entire North Atlantic and its adjacent seas, primarily the Mediter-ranean Sea. ICCAT recognizes two stocks: Western Atlantic, and eastern Atlantic and Mediterranean bluefin. There is considerable mixing between the two.

Western Atlantic bluefin catches in 2014 were about 1,600 tonnes, a 9% increase from 2013. Sport gears (hand line, rod-and-reel) take 49% of the catch, followed by longline (41%) and other surface gears. Purse seine catches in recent years have been very minor (Figure AO-17).

Figure AO-17. Catches of Western Atlantic bluefin tuna from 1950 to 2014, by gear type.

S T O C K A S S E S S M E N T In 2014, ICCAT’s SCRS conducted an update of the 2012 assessment of western Atlantic bluefin applying the same methodologies and hypotheses adopted by the Committee in 2012 and catch, effort and size statistics through 2013. The stock assessment model estimates that recruitment in the early 1970s was very high compared to the level estimated since the 1980s. The assessment also indicates spawning stock biomass was also much higher in the 1970s and earlier compared to the levels estimated since the 1980s. In calculating the status of the stock relative to MSY reference points, the SCRS considers two alterna-tive hypothesis: One is that the high recruitment levels of the 1970s can be achieved again if the stock is allowed to rebuild substantially; the other hypothesis is that there has been a "regime shift" and envi-ronmental conditions can no longer support those high levels of recruitment, even if the stock is allowed to rebuild. These two are known as "high potential recruitment" and "low potential recruitment" hy-potheses. Using these, the SCRS concluded the following (Figure AO-18):

1. The current ratio of spawning biomass Bcurrent/BMSY is estimated at 0.48 (assuming high potential recruitment) or 2.2 (assuming low potential recruitment). Thus, the stock is either severely overfished, or not overfished at all, depending on the assumed level of potential recruitment.

2. The ratio of Fcurrent/FMSY is estimated at 0.88 (assuming high potential recruitment) or 0.36 (as-suming low potential recruitment). Thus, overfishing is no longer taking place with assumed re-cruitment in either scenario.

3. The estimate of MSY is 5,300 tonnes (assuming high potential recruitment) or 3,000 tonnes (as-suming low potential recruitment.

Clearly, the status of the western Atlantic bluefin stock is highly dependent on the potential recruitment assumption. For years, the SCRS has been unable to give an idea about which of the two assumptions is

AO-BFT-W


more plausible. ISSF considers that SCRS should revisit this issue as a matter of priority so that it can provide unambiguous advice that is based on one of the two assumptions. Until then, given the lack of clear indication of a regime shift, ISSF believes that it is more precautionary to assume that the high-recruitment hypothesis applies and that the stock can be rebuilt to the higher levels estimated in the 1960s and 1970s. As a result, ISSF considers that the western Atlantic bluefin stock is still overfished, but that overfishing is no longer occurring.

Figure AO-18. Temporal trend in the median ratios Bcurrent/BMSY (x-axis) and Fcurrent/FMSY (y-axis) for western Atlantic bluefin tuna assuming two levels of potential recruitment. The symbols represent uncertainty in the estimate of the current ratios.


Target reference point: Not defined for the long term. "Green" quadrant in Kobe plot implied as target (Rec. 11-13). Interim target is to achieve BMSY through 2018 with at least 50% probability (Rec. 13-09).


Western Atlantic bluefin has been the subject of a rebuilding program since 1998 (ICCAT Rec. 98-07), which has been amended in every other year since 2002. The plan in Recommendation 14-05 aims to rebuild the stock by 2018 with at least 50% probability, mainly through TACs (the 2015 and 2016 TACs are 2,000 tonnes each year). The management plan also establishes a 30-kg minimum size and prohibits directed fisheries in the Gulf of Mexico (the only known spawning area for the stock).

AO-BFT-W


S U M M A R Y

AO BFT-W Estimate Years Notes

Recent catch 1.6 2014

5-yr catch 1.7 2010-14

MSY 5.3 2013

F/FMSY 0.88

2010-2012

B/BMSY 0.19 2013

TAC 2 2015 and 2016


STOC K AB UND ANC E

B < BMSY. Stock biomass is very low under the "high potential recruit-ment" hypothesis.


F < FMSY..

ENV IRONM ENT 49% of the catch is made by sport fishing gears (rod-and-reel, handline) with minor amounts of bycatch.

41% of the catch is made by longlining. Several mitigation measures are in place.

Last date of a change in Color Ratings: February, 2015. Changes from the previous (original) Color Ratings: The Fishing mortality rating changed from Orange to Green.

IO


S T OCKS I N T HE I ND I AN OCE A N RFMO: Indian Ocean Tuna Commission (IOTC). The stocks are assessed by the IOTC SC, which makes recommendations to the IOTC.

Last Scientific Committee (SC) meeting: December, 2014

Last Commission meeting: April, 2015.

Tuna stocks managed by IOTC: IO Yellowfin, IO Bigeye, IO Skipjack, IO Albacore.

Data sources: The main sources of information for this section IOTC (2014), IOTC (2015).


About 20 percent of the world production of tuna is from the Indian Ocean (IO), making this the second largest region for tuna fishing after the western and Central Pacific Ocean. Catches of skipjack, yellow-fin, bigeye and albacore in 2013 were 974,300 tonnes, a 9% increase from 2012. There has been a gen-eral tendency for the total catch to decline since 2005, when a record 1.2 million tonnes were caught, followed by an increase in recent years (Figure IO-1). Catches of southern bluefin tuna occur substantial-ly in the IO Convention Area. This stock is covered in a different section of this report, under Southern Hemisphere.

Figure IO-1. Trends in catch (mt) of bigeye, skipjack, yellowfin and albacore in the IO region, by species (left) and gear (right),

1950-2013.

Average catches for the five-year period 2009-2013 (883,900 tonnes) provide an indication of the recent performance of the fisheries (Figure III.1.2): Skipjack accounts for 45.4% of the catches in weight, fol-lowed by yellowfin (38.4%), bigeye (12%), and albacore (4.2%). Purse-seine vessels take about 36% of the total catch, followed by gillnets (18%), longline (18%) and pole-and-line (11%). Gillnet fisheries are gener-ally poorly monitored.

Figure IO-2. Average 2009-2013 catches of skipjack, yellowfin, bigeye and albacore in the IO. The graph on the left shows

the percentages by species, and the graph on the right shows the percentages by gear type.

IO-BET


IO Bigeye Tuna Bigeye reported catches in 2013 were about 109,300 tonnes, an 8% decline from 2012. The main fishing gear is longline (57%). Catches by this gear have declined dramatically from a high in 2004 (Figure IO-3), due to vessels moving away from the main fishing grounds to escape piracy, but increased sharply in 2012 only to decrease again in 2013. In contrast, catches from purse seine vessels (28%) have been relatively stable since 2000.

Figure IO-3. Catches of bigeye tuna in the IO from 1950 to 2013, by gear type.

S T O C K A S S E S S M E N T The 2013 assessment conducted by the Scientific Committee (SC15) gave similar tendencies to the 2010 and 2011 assessments in terms of average trends. The results of the new assessment indicated the fol-lowing (Figure IO-4):

1. The ratio of Fcurrent/FMSY is estimated to be 0.42 (range: 0.21 to 0.80), indicating that overfishing is not occurring.

2. The ratio of spawning biomass Bcurrent/BMSY is 1.44 (range: 0.87 to 2.2), indicating that the stock is not in an overfished state.

3. The estimate of MSY is 132,000 tonnes. The 2013 catch was below this level.

Resolution 13/10 established interim limit reference points for bigeye as 0.5BMSY and 1.3FMSY. These are not being exceeded.

IO-BET


Figure IO-4. Temporal trend in the ratios Bcurrent/BMSY (x-axis) and Fcurrent/FMSY (y-axis) for bigeye tuna in the IO. Purple circles represent the annual median values over time. Dots indicate uncertainty in the current status estimated from models that make different assumptions. Colors are taken from IOTC reports and do not necessarily correspond to the colors used for

ratings in the ISSF Stock Status Report.

M A N A G E M E N T Limit reference point: Interim limits of 0.5BMSY and 1.3FMSY (Resolution 15/10). Resolution 14/03 requires a series of Science and Management Dialogue Workshops to advance work on the adoption of reference points and harvest control rules.

Target reference point: Interim targets of BMSY and FMSY (Resolution 15/10).

Harvest control rule: Not defined yet. Resolution 15/10 requests the SC to develop HCRs designed to maintain or restore stocks to the "Green" quadrant of the Kobe plot.

There are no conservation measures established by the IOTC for bigeye. Resolution 14/02, calls for members to implement a quota allocation system based on recommendations from the scientific com-mittee, but it is not clear how this will be done. Resolution 15/06 establishes a ban on discards of bigeye, skipjack and yellowfin tuna by purse seine vessels.

IO-BET


S U M M A R Y

IO BET Estimate Years Notes


5-yr catch 106 2009-13

MSY 132 2012

F/FMSY 0.42

2012

B/BMSY 1.44 2012

TAC N/A


STOC K AB UND ANC E

B > BMSY.


F < FMSY.




14% of the catch is made by other gears such as gillnet. There is poor reporting by these fisheries which are thought to have substantial amounts of bycatch.


IO-YFT


IO Yellowfin Tuna Yellowfin catches in 2013 were about 402,100 tonnes, a 0,5% increase from 2012. The main fishing gears for which catches have declined recently are purse seine (35% of the catch) and longline (18%) (Figure IO-5). In contrast, catches by gillnet (16%) and miscellaneous gears (26%) have become increasingly im-portant in recent years. Catches by these gears are poorly estimated. Catches from pole-and-line ves-sels (5%) have been relatively stable. Overall, catches have declined by 24% from a record high of 530,000 tonnes in 2004.

Figure IO-5. Catches of yellowfin tuna in the IO from 1950 to 2013, by gear type.

S T O C K A S S E S S M E N T The 2012 updated assessment using two different models gave similar results to the 2011 assessment, indicating the following (Figure IO-6):

1. The ratio of Fcurrent/FMSY is estimated at 0.61 or 0,69 depending on the model, indicating that overfishing is not occurring. The trajectories explained by the two models differ in that one of them suggests that FMSY was exceeded during the period of high catches of yellowfin tuna from 2003 to 2006, while the other model does not. However, both models estimate a similar status at the present time.

2. The stock is not in an overfished state as spawning biomass is above the BMSY level (Bcurrent/BMSY = 1.24 to 1.35, depending on the model).

3. The value of MSY is estimated to be 320,000 to 344,000 tonnes depending on the model. During the period 2003-2006, catches substantially exceeded this level and the stock experienced a rap-id decline. In 2013, catches exceeded MSY.

Resolution 13/10 established interim limit reference points for yellowfin as 0.4BMSY and 1.4FMSY. These are not being exceeded.

IO-YFT


Figure IO-6. Temporal trend in the ratios Bcurrent/BMSY (x-axis) and Fcurrent/FMSY (y-axis) for yellowfin tuna in the IO. The two

graphs correspond to two different models (the value in the last year is very similar for both models). Colors are taken from IOTC reports and do not necessarily correspond to the colors used for ratings in the ISSF Stock Status Report.




There are no conservation measures established by the IOTC for yellowfin. Resolution 14/02, calls for members to implement a quota allocation system based on recommendations from the scientific com-mittee, but it is not clear how this will be done. Resolution 15/06 establishes a ban on discards of bigeye, skipjack and yellowfin tuna by purse seine vessels.

The IO yellowfin stock has been of concern because the catches in 2003-2006 substantially exceeded the MSY level. Since then, catches have decreased considerably and the 2011 SC estimated that the stock was in good health. However, this trend could be easily reversed if the piracy situation in the IO im-proves and fishing effort increases. The 2013 catch exceeds the MSY level by 17%.

IO-YFT


S U M M A R Y

IO YFT

Estimate Years Notes


5-yr catch 339 2009-13

MSY 320-344 2011

F/FMSY 0.61-0.69

2011

B/BMSY 1.24-1.35 2011

TAC N/A


STOC K AB UND ANC E

B > BMSY. The 2012 assessment indicates that the stock is in a healthy state. Declines in biomass due to intensive fishing in the mid-2000s have been halted with reduced catches. However, the 2012 catch exceeded the MSY level and stock status should be reassessed.


F < FMSY. If fishing effort displaced because of the piracy problem returns to traditional fishing areas, an increase in F could be expected. The situation needs to be monitored closely.

ENV IRONM ENT 16% of the catch is made by gillnets, which are poorly monitored. Gill-nets are thought to have high bycatch rates. No mitigation measures are in place and monitoring is extremely deficient.




16% of the catch is made by handlines, expected to have little impact on bycatch species.

7% of the catch is made by trolling, expected to have little impact on bycatch species.

5% of the catch is made by pole-and-line fishing, with small bycatch of non-target species but unknown impacts on baitfish stocks.

Last date of a change in Color Ratings: December, 2011. Changes from the previous (original) Color Ratings: The Biomass rating changed from Yellow to Green.

IO-SKJ


IO Skipjack Tuna Skipjack catches in the Indian Ocean in 2013 were about 424,600 tonnes, a 26% increase from 2012. Purse seine (42%) and gillnets (26%) dominate the catches, followed by pole-and-line (20%) (Figure IO-7). Pole-and-line, purse seine and gillnet catches have been decreasing since the mid-2000s.

Figure IO-7. Catches of skipjack tuna in the IO from 1950 to 2013, by gear type.

S T O C K A S S E S S M E N T The most recent stock assessment of skipjack was conducted in 2014 and did not differ substantially from the previous (2011 and 2012). The results indicate that (Figure IO-8):

1. The ratio of Fcurrent/FMSY current proxies is estimated to be 0.62. Therefore, overfishing is not oc-curring.

2. The stock is not in an overfished state as spawning biomass is above the BMSY level (Bcurrent/BMSY = 1.59, range: 1.13-2.14).

3. The median estimate of MSY is estimated to be 684,000 tonnes (range: 550,000 to 849,000 t).

Recommendation 13/10 established interim limit reference points for skipjack as 0.4BMSY and 1.5FMSY. These are not being exceeded.

Figure IO-8. Temporal trend in the ratios Bcurrent/B0 (x-axis) and Fcurrent/FMSY (y-axis, using catch as a proxy) for skipjack tuna in the IO. Blue circles indicate the median trajectory. Contours are the 50, 70 and 90 percentiles of the 2013 estimate. Colors are taken from IOTC reports and do not necessarily correspond to the colors used for ratings in the ISSF Stock Status Report.

IO-SKJ





There are no conservation measures established by the IOTC for skipjack. Resolution 14/02, calls for members to implement a quota allocation system based on recommendations from the scientific com-mittee, but it is not clear how this will be done. Resolution 15/06 establishes a ban on discards of bigeye, skipjack and yellowfin tuna by purse seine vessels.

S U M M A R Y

IO SKJ Estimate Years Notes


5-yr catch 401 2009-13

MSY 684 2013

F/FMSY 0.62

2013 C2013/CMSY

B/BMSY 1.59 2013

TAC N/A


STOC K AB UND ANC E

B > BMSY.


F < FMSY.

ENV IRONM ENT 26% of the catch is made by gillnets, a gear expected to have high by-catch rates. No mitigation measures are in place and monitoring is ex-tremely deficient.


20% of the catch is made by pole-and-line fishing, with small bycatch of non-target species but unknown impacts on baitfish stocks.


Last date of a change in Color Ratings: December, 2011. Changes from the previous (original) Color Ratings: The Biomass rating changed from Yellow to Green.

IO-ALB


IO Albacore Tuna Albacore catches in the Indian Ocean in 2013 were about 38,300 tonnes, a 15% increase from 2012. Almost all catches are made by drifting longlines (Figure IO-9).

Figure IO-9. Catches of albacore tuna in the IO from 1950 to 2013, by gear type.

S T O C K A S S E S S M E N T The latest assessment was performed by the SC in 2014. The conclusions from the assessment are more optimistic than those of 2012 and indicate that (Figure IO-10):

1. The ratio of Fcurrent/FMSY is estimated to be 0.69 (range: 0.23 - 1.39, according to one model) and 0.94 (range: 0.68 – 1.61, according to a second model). Therefore, overfishing is not likely occur-ring. Piracy in the western tropical Indian Ocean displaced much of the longline fishing effort to the South and East, which are traditional fishing grounds for albacore.

2. The stock is not in an overfished state as spawning biomass is slightly above the BMSY level (Bcur-

rent/BMSY = 1.09 or 1.05, using two models).

3. The median estimate of MSY is estimated to be between 34,700 and 47,600 tonnes, depending on the model used.

Figure IO-10. Temporal trend in the ratios Bcurrent/BMSY (x-axis) and Fcurrent/FMSY (y-axis) for albacore tuna in the IO. Circles

indicate the median trajectory and the probability distribution contours are provided as a rough visual guide of the uncertainty in current (2012) estimates. Colors are taken from IOTC reports and do not necessarily correspond to the colors used for

ratings in the ISSF Stock Status Report.

IO-ALB





There are no conservation and management measures adopted by IOTC for albacore.

S U M M A R Y

IO ALB Estimate Years Notes


5-yr catch 38 2009-13

MSY 34.7-47.6 2012

F/FMSY 0.69-0.94

2012

B/BMSY 1.05-1.09 2012

TAC N/A


STOC K

AB UND ANC E

B > BMSY. However there is considerable uncertainty in the assessment results.


F < FMSY. However, there is considerable uncertainty in the assessment results. The SC has recommended a reduction in fishing mortality or to limit catches to 34,000 tonnes (about 11% below the 2013 level).

ENV IRONM ENT Almost 100% of the catch is made by longlining. Several mitigation measures are in place (sharks, turtles, sea birds). Monitoring is deficient.

Last date of a change in Color Ratings: February, 2015. Changes from the previous (December 2012) Color Ratings: Fishing mortality rating was changed from Orange to Yellow to reflect the more optimistic results of the updated 2014 assessment.

SBT


S OUT HE R N HE M I S PHE RE ST OCKS RFMO: Commission for the Conservation of Southern Bluefin Tuna (CCSBT). The stock is as-sessed by the SC who makes recommendations to the CCSBT.

Last Scientific Committee meeting: September, 2014.

Last Commission meeting: October, 2014.

Tuna stocks managed by CCSBT: Southern bluefin tuna.

Data sources: The main sources of information for this section CCSBT (2014).

Last update: February, 2015.

SH Southern Bluefin Tuna Southern bluefin tuna (Thunnus maccoyii) is found in the southern hemisphere, mainly in waters between 30° and 50° S. The stock is assessed and managed by the Commission for the Conservation of Southern Bluefin Tuna (CCSBT). While the IATTC, ICCAT, IOTC and WCPFC have in principle a mandate to manage all tunas in their respective Convention Areas, in practice they defer to CCSBT for management of southern bluefin. Practically all of the catches are made in the IOTC, ICCAT and WCPFC convention areas (79% in the Indian Ocean, 17% in the Pacific Ocean and 4% in the Atlantic Ocean).

Southern bluefin catches in 2013 were about 11,700 tonnes, a 14% increase from 2012. Virtually all of the catches are made by longline (58%) and purse seine (42%). Current catches are nearly one-tenth of what they were at their peak, in 1961. (Figure I.2.1.1).

Figure SH-1. Catches of southern bluefin tuna from 1952 to 2013, by gear type.

S T O C K A S S E S S M E N T Southern bluefin tuna is assessed by the Extended Scientific Committee (ESC) of the CCSBT. In 2014, the ESC indicated the following (Figure SH-2):

1. The current ratio of spawning biomass Bcurrent/BMSY is estimated at 0.38 (range: 0.26-0.70). This indicates that the stock is in a severely overfished state. Spawning biomass is estimated to be be-tween 8% and 12% of the unfished level.

SBT


2. The ratio of Fcurrent/FMSY is estimated at 0.66 (range: 0.39-1.00), indicating that overfishing is not occurring. While overfishing was taking place in recent years, current fishing mortality has been reduced below the MSY level following reductions in overall catch.

3. The estimate of MSY is 33,000 tonnes.

Figure SH-2. Temporal trend in the median ratios Bcurrent/BMSY (x-axis) and Fcurrent/FMSY (y-axis) for southern bluefin tuna. Verti-cal and horizontal lines provide an idea of the relative uncertainty in the estimates. Colors are taken from CCSBT reports and

do not necessarily correspond to the colors used for ratings in the ISSF Stock Status Report.


Target reference point: Not defined for the long-term. 20% of the unfished biomass (20%SB0) is used as an interim target to be achieved with 70% probability by 2035.

Harvest control rule: Harvest rules via a TAC, that is the average catch value from two formulas de-signed to achieve the recovery target and tuned to juvenile surveys and CPUE. 0.7 probability of rebuild-ing to 20%SSB0.

Southern bluefin tuna is managed primarily through annual TACs that aim, as an interim target, to rebuild the stock to 20% of the unfished level by 2035. The TACs are set through a process known as a Man-agement Procedure (MP), adopted in 2011, that specifies the actions to be taken depending on the out-comes of the assessment made by the ESC (in essence, a Harvest Control Rule).

TACs under the MP are set for three-year periods to maintain the stock on the planned rebuilding tra-jectory. The MP specifies the minimum and maximum permissible changes in TAC (either increase or decrease, depending on stock status relative to the rebuilding trajectory). For the three year period 2015-2017, the TAC is set to 14,647 tonnes.

SBT


S U M M A R Y

SBT Estimate Years Notes

Recent catch 11.7 2013

5-yr catch 10.4 2009-13

MSY 33 2013

F/FMSY 0.66

2013 Range: 0.39-1.00

B/BMSY 0.38 2014 Range: 0.26-0.70

TAC 14.6 2015-2017


STOC K

AB UND ANC E

B << BMSY. Stock abundance is very low, about 9% of the unfished level.


F < FMSY.

ENV IRONM ENT 58% of the catch is made by longlining. Several mitigation measures are in place (sea birds).

42% of the catch is made by purse seining on free schools of southern bluefin.

Last date of a change in Color Ratings: February, 2015. Changes from the previous (original) Color Ratings: The F rating changed from Yellow to Green, as the last two assessments indicate F<FMSY.


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Schaefer, K., D. Fuller, J. Hampton, S. Caillot, B. Leroy and D. Itano. 2014. Movements, dispersion, and mixing of bigeye tuna (Thunnus obesus) tagged and released in the equatorial Central Pacific Ocean, with conventional and archival tags. Fisheries Research 161(2015) 336-355.

SPC/OFP. 2008. Estimates of annual catches in the WCPFC statistical area. Document WCPFC-SC4-2008/ST-IP-1 (distributed at the 2008 meeting of the Scientific Com-mittee of the WCPFC).

SPC/OFP. 2010. Non-Target Species Interactions with the Tuna Fisheries of the Western and Central Pacific Ocean. Document WCPFC-SC6-2010/EB-IP-8 (distribut-ed at the 2010 meeting of the Scientific Committee of the WCPFC).

WCPFC. 2015. Executive Summary of the Eleventh regular session of the Scientific Committee. Pohnpei, Fed. States of Micronesia, 5-13 August 2015.

WCPFC. 2015b. Estimates of annual catches in the WCPFC statistical area. Document WCPFC-SC11-2015/ST IP-1.


G L OS S ARY A ND A CR ONY MS TERM ME ANIN G

AIDCP The Agreement on the International Dolphin Conservation Program

ALB Albacore tuna, Thunnus alalunga.

AO Atlantic Ocean

BET Bigeye tuna, Thunnus obesus.

BFT Atlantic bluefin tuna, Thunnus thynnus.

BMSY (also "Biomass at MSY" or "MSY Biomass Level"). This is the stock size (biomass) that would result on average if FMSY was applied constantly year after year. BMSY is sometimes measured by the total biomass of the stock and sometimes by the biomass of the spawners ("spawning biomass", or SSB).

CCSBT Commission for the Conservation of Southern Bluefin Tuna (www.ccsbt.org)

EPO Eastern Pacific Ocean

F Instantaneous fishing mortality rate, a measure of the intensity with which a stock is being exploited. The catch of a stock is roughly proportional to F multiplied by abundance.

FAD Fish Aggregating Device. An inanimate object that attracts tunas and other marine life. In this report, "FAD" is used broadly for natural logs, as well as man-made objects, both anchored and drifting.

FMSY (also "Fishing Mortality at MSY" or "MSY Fishing Mortality Level"). This is the level of fishing intensity that, if applied constantly year after year, would result in MSY.

IATTC Inter-American Tropical Tuna Commission (www.iattc.org)

ICCAT International Commission for the Conservation of Atlantic Tunas (www.iccat.int)

IO Indian Ocean

IOTC Indian Ocean Tuna Commission (www.iotc.org)

ISC International Scientific Committee for Tuna and Tuna-like Species in the North Pacific Ocean (isc.ac.affrc.go.jp)

MSY The largest average catch or yield that can continuously be taken from a stock under existing environmen-tal conditions. (For species with fluctuating recruitment, the maximum might be obtained by taking fewer fish in some years than in others.)

PBF Pacific bluefin tuna, Thunnus orientalis

PNA Parties to the Nauru Agreement

PO Pacific Ocean

RFMO Regional Fishery Management Organization

SBT Southern bluefin tuna, Thunnus maccoyii

SH Southern hemisphere

SIDS Small Island Developing States

SKJ Skipjack tuna, Katsuwonus pelamis

SPC/OFP Secretariat of the Pacific Community (Oceanic Fisheries Programme)

SSBMSY See BMSY.

http://www.pnatuna.com/


Stock In general, a stock is a biological unit of one species forming a group of similar ecological characteristics and, as a unit, is the subject of assessment and management. However, there are many uncertainties in defining spatial and temporal geographical boundaries for such biological units that are 100% compatible with established tuna RFMO Convention Areas. The stocks listed in this report correspond to the assess-ment/management units established by the tuna RFMOs, even if there is migration of the same species to and from adjacent areas.

Stock As-sessment

The application of statistical and mathematical tools to relevant data in order to obtain a quantitative un-derstanding of the status of the stock relative to management benchmarks (e.g. BMSY) as needed to make quantitative predictions of the stock´s reactions to alternative management measures.

TAC Total Allowable Catch

WCPFC Western and Central Pacific Fisheries Commission (www.wcpfc.int)

WCPO Western and Central Pacific Ocean

YFT Yellowfin tuna, Thunnus albacares


A PPE ND I X 1 . BY CAT CH

Impacts by gear type All fishing gears have some level of environmental impact, and bycatch is one of the most noticeable ones. This summary presents the overall ratings given by default to various gear types. Deviations from these color ratings may occur for individual stocks, due to advice from the ISSF Scientific Advisory Committee; these are noted for each particular stock in which deviations may occur.

This summary is presented only for non-target (non-tuna) species. Note that in some ocean regions, fishing modes such as FAD-based purse seining and pole-and-line fishing can result in high catches of small individuals of bigeye and yellowfin, which are undesirable. In this stock status report, these impacts are measured directly under the status section for these stocks.

Sources of information used for these ratings include the following: Amandè et al. (2010), Clarke and Harley (2010), FAO (2009), Gillett (2011), Gilman (2011), Harley, et al. (2011), IATTC (2012), IOTC (2005), IOTC (2015), Matsumoto and Bayliff (2008), Morizura el al. (1999), Olson (2010), Pianet et al. (2010a), Pianet et al. (2010b), SPC/OFP (2008), SPC/OFP (2010) and Justel-Rubio and Restrepo (2015).

Gillnet fishing.

Gillnet fisheries take substantial amounts of tunas in various ocean regions, especially in the Indian Ocean. For the most part, these are poorly monitored but it is known that they tend to catch many different species at the same time. By-catch rates of many non-target species tends to be high. Large-scale driftnets are generally prohibited on the high seas but appear to continue to be used. Sharks. Silky, oceanic whitetip and scalloped hammerhead sharks are common in gillnet fisheries. All of these species are of concern because of their low productivity and vulner-ability to overfishing. Sea Turtles. Sea turtle bycatch is thought to be highest in gillnet fisheries compared to other gears. Sea birds. The incidental catch of sea birds in gillnet fisheries is largely unknown. Other finfish. Gillnet operations catch a number of other finfishes. Some of these include very productive species such as dolphinfish ("mahi-mahi") that are not of immediate con-cern.

Handlines.

This mode of fishing typically results in small bycatch rates.

Longlining.

Sharks. Longline fisheries tend to have very high catch rates of sharks (in some areas, 30% of the longline catches are sharks). In some cases the sharks can be a target of the

fishing operations, at least for parts of a trip. Sharks caught include a wide range of species, some of which are thought to be resilient to fishing (blue shark), and others which are likely to be more vulnerable because of their low reproduc-tive rates (e.g., porbeagle and thresher sharks). Sea Turtles. Some turtles are also caught in longline opera-tions as bycatch, many of which are discarded (including live releases). All RFMOs have some type of mitigation measure in place. Roughly one half, or more, of the turtles caught are alive, so the main mitigation measures aim to dehook them and release them alive. Sea birds. Some sea birds are also caught in longline opera-tions as bycatch, especially in higher latitudes. Most (~90%) sea birds caught are dead when brought onboard, so the best practice for mitigation is to avoid their being hooked, which is the main type of mitigation measure used by the RFMOs. Of particular concern are albatrosses and petrels. Other finfish. After tunas and sharks, longline operations catch a number of other finfishes. Some of these include very productive species such as dolphinfish ("mahi-mahi") that are not of immediate concern. Longlining also catches marlins, some of which are estimated to be overfished.

Mid-water trawling.

This mode of fishing has a small bycatch rate of cetaceans.

Pole-and-line fishing.

There are no major concerns with the catch of vulnerable non-target species by this gear. However, the method re-quires the use of live baitfish (small pelagics) that are used to


keep the schools of tunas attracted to the fishing vessels while they are fished. The effects of fishing on these popula-tions is largely unknown; however, they should be managed in order to support pole and line fisheries. Gillett (2011) notes that the amount of baitfish available in the WCPO is a limiting factor to the amount of pole and line fishing that can occur. In addition, the bait species captured are generally more fragile than temperate baitfish species.

Purse seining on free schools.

This mode of fishing typically results in small bycatch rates of non-target species.

Purse seining on FADs.

Purse seining on FADs (anchored FADs, drifting FADs and natural logs) generally has bycatch rates of non-target spe-cies that are higher than those of free school sets. Sea Turtles. The number of turtles that die in purse seine fishing operations is very small. Nevertheless, it is relatively easy to release turtles when caught alive and this is the main mitigation measures used by RFMOs. Sharks. FAD purse seine fishing operations catch several species of sharks, some of which, based on catch trends, may have been declining in abundance in recent years, such as oceanic white tip and silky sharks. Entanglement can be a significant problem, especially if FAD designs use underwater netting materials with large mesh sizes. ISSF is advocating for RFMOs to require non-entangling designs. Sea birds. Mortality of other sensitive species like seabirds in FAD operations is almost nonexistent. Other finfish. FAD fishing does result in large catches of other finfish such as dolphinfish ("mahi-mahi"). Currently, it appears that these catches do not adversely impact the abundance of these species which are very productive and resilient to fishing. Rather, the main problem with these bycatches is one of utilization (waste), since the majority of these are discarded at sea so that the fish holding tanks can be reserved for the more valuable tunas.

Purse seining on tuna-dolphin associations.

Marine mammals. In the EPO, purse-seine fishermen have learned to take advantage of the association between yellow-fin schools and herds of dolphins that is prevalent in the region. Fishermen maximize their catches of yellowfin by setting their nets around these associations. Mortality of dolphins was very high early on, but the IATTC estimates that it has since the late 1980s declined by 98% after fisher-men and scientists developed techniques for releasing the dolphins alive after a set, and retaining the tunas. Some scientists believe that there is an un-quantified level of mor-tality after the sets, caused by stress, and this remains a controversial issue. Based on fishery-independent surveys, the abundance of most dolphin populations in the region was estimated to be either stable or increasing, while a few may have been declining. The last such survey was in 2006 and as a result there is uncertainty in the current status of those populations. Thus, the rating for this fishing method has changed from Green to Yellow (November, 2015). The Agreement on the International Dolphin Conservation Pro-gram (AIDCP) establishes allowable dolphin mortality limits; current (2011) levels are one-fourth of that level. There is a 100%-coverage observer program in place for these opera-tions. Catches of non-target species in these operations are very small.

Trolling.

This mode of fishing typically results in very small bycatch rates of non-target species.

Tuna traps. Migrating schools of bluefin tuna have been caught by traps that are fixed near the shoreline, especially in the eastern Atlantic and Mediterranean. Most of the catch in these traps consists of scombrids, including bluefin, and up to 99% of it is utilized. There are no major bycatch issues known with this passive gear, although it occasionally catches sharks.

RFMO bycatch mitigation and monitoring The following is a summary of the major mitigation and monitoring measures adopted by the various tuna RFMOs. CCSBT Sea birds, sharks and turtles: With only one exception, all CCSBT Members and Cooperating Non-Members are also Parties or Cooperating Parties to IOTC, WCPFC and/or

ICCAT. As a consequence, any binding bycatch mitigation measure of these RFMOs is in practice binding on the CCSBT Member/Cooperating Non-Member when fishing within that Convention Area. Additionally, the non-binding


Recommendation to Mitigate the Impact on Ecologically Related Species - ERS - of Fishing for Southern Bluefin Tuna (updated 2011) strongly encourages CCSBT members to comply with mitigation measures on sea birds, sharks and sea turtles adopted by ICCAT, IOTC and WCPFC. Sea birds. Mandatory use of Tori poles is required by all members in all southern bluefin longline fisheries South of 30°S. Monitoring and mitigation research. CCSBT members are required to exchange information concerning new or refined techniques to reduce incidental catch of seabirds and coop-erate in developing and assessing the effectiveness of such techniques. Most CCSBT Members and Cooperating Non-Members have achieved 10% scientific observer coverage (in catch and effort) for their fisheries; the 10% level is a non-binding target. IATTC General: Resolution 04-05 requires the release of non-target species caught in purse seine fisheries. Sea Turtles. Resolution C-07-03 requires fishermen to re-lease sea turtles entangled in FADs or caught in longlines and to avoid encircling them with purse seine nets. The resolu-tion also calls for research to mitigate sea turtle bycatch, especially with gear modifications. Resolution C-15-03 calls for a transition to non-entangling FADs in purse seine fisher-ies. Sharks. Resolution C-05-03 discourages shark retention and establishes a limit in the amount of shark fins that can be landed, relative to the total weight of shark bodies that must be retained. This ratio of fin-to-body-weight acts as a disin-centive to target sharks because the shark carcasses occupy hold space on the vessel and have little market value. The Resolution also mandates reporting of shark catches to IATTC. Resolution C-11-10 prohibits the retention of oce-anic whitetip sharks and requires the release of specimens that are alive when caught. Resolution C-15-03 calls for a transition to non-entangling FADs in purse seine fisheries and prohibits deliberate setting on whale sharks. Rays. Resolution C-15-04 requires CPCs to prohibit retain-ing onboard, transshipping, landing, storing, selling, or offer-ing for sale any part or whole carcass of Mobulid rays and to release all Mobulid rays alive wherever possible. Sea birds. The IATTC Resolution C-11-02 requires longline vessels operating in high latitudes (North of 23°N, South of 30°S and around the Galapagos Islands) to employ at least two sea bird mitigation techniques such as night setting or weighted branch lines. Dolphins. The AIDCP establishes total per-stock and per-year limits on incidental dolphin mortality (DMLs), with a structured protocol for allocating and keeping track of DMLs (using observers). A vessel must stop setting on dolphin associations for the rest of the year once its DML has been reached. Monitoring and mitigation research. Through the Agreement on the International Dolphin Conservation Program (AIDCP), there is 100% observer coverage on all large purse seiners (> 363 tons in carrying capacity) and lower coverage on smaller vessels. This level of observer coverage, coupled with the information from fishing logbooks, allows the IATTC to maintain a very complete accounting of the by-catch taken in purse seine fisheries in the EPO. Several

IATTC Recommendations and Resolutions encourage re-search that could make FAD-based purse seining and longlin-ing more species-selective. These are non-binding, however, and depend on the IATTC member nations making the necessary resources available. ISSF has a research program for bycatch mitigation in purse seine fisheries, and IATTC scientists are taking part in this program (IATTC, 2010). Resolution C-11-08 now requires 5% scientific observer coverage for large longliners.

NOTE: Major fleets such as Japan that use longlining in the EPO reported catches of non-target species to IATTC (par-ticularly sharks and billfishes; Matsumoto and Bayliff, 2008), and in this sense they were relatively better than longline fleets elsewhere. However, it is apparent that this level of monitoring and reporting has not been maintained. ICCAT General: Recommendation 14-01 requires a transition to non-entangling FADs. Sharks: Recommendation 04-10 established a limit on the ratio of fin weight to total shark weight that can be retained onboard a fishing vessel, and encouraged the release of live sharks in fisheries that do not target sharks. Recommenda-tion 07-06 limits mortality on porbeagle and North Atlantic shortfin mako. Recommendation 14-06 aims to improve data collection and reporting for SMA. Recommendations 09-07, 10-07, 10-08 and 11-08 prohibit the retention on board of bigeye thresher, oceanic white tip, several species of ham-merhead sharks, and silky sharks. All of these measures have a reporting requirement associated with them (Recommen-dation 12-05 requires all parties in 2013 to report on their compliance with Recs. 04-10, 07-06, 09-07, 10-08, 10-07, 11-08, and11-15). Recommendation 10-06 prohibits the reten-tion of shortfin mako onboard vessels flagged to countries that do not report catches for this species. Sea Turtles. Recommendations 10-09 and 13-11 set up reporting requirements for sea turtle interactions and man-dates its scientific committee to assess, by 2014, the impact of tuna fisheries on sea turtle populations. The measure has specific requirements for longline operators to be trained on appropriate handling and release of live turtles so as to maximize their survival. Sea birds. Recommendation 07-07 required longliners oper-ating south of 20°S to use at least two of several mitigation measures such as weighted branch lines or tori (bird-scaring) lines. The measure also required ICCAT members to collect and report data on interactions between fisheries and sea birds. Recommendation 11-09 strengthened the mitigation measures in 07-07, especially for longliners fishing south of 25°S, and in the Mediterranean. Other finfish. Longliners and other fisheries also take Atlan-tic blue and white marlin as bycatch, both of which are thought to be overfished. ICCAT adopted Recommendation 06-09, later superseded by 12-04, a rebuilding plan with catch limits by country. Monitoring and mitigation research. ICCAT has specific requirements for reporting data on sharks, sea turtles and sea birds. For the most part these are not complied with fully, but the situation is improving over time. Recommenda-tion 10-10 requires members to have at least 5% observer coverage (for vessels over 15 m) in their national observer


programs for longline, purse seine and pole-and-line fisher-ies. Recommendation 11-10 requires CPCs to collect and report data on bycatch and discards either through observer programs and logbooks (for vessels to which Rec. 10-10 applies) or via alternative means (for artisanal and semi-industrial fisheries). Recommendation 11-15 establishes penalties for CPCs that do not report annual catch data (including zero catches) by prohibiting them from retaining such species in the following year. IOTC Sharks: The IOTC has adopted measures that address shark conservation concerns. Resolution 05/05 established a limit on the ratio of fin weight to total shark weight that can be retained onboard a fishing vessel, and encouraged the re-lease of live sharks in fisheries that do not target sharks. Resolution 12/09 prohibits the retention on board of all species of thresher sharks, a group that is thought to be particularly vulnerable due to its low productivity. In addi-tion, Resolution 12/09 requires data reporting to IOTC, especially for fisheries targeting sharks. Resolution 13/05 prohibits intentional purse seine setting on tunas associated with whale sharks. Resolution 13/06 prohibits the retention of oceanic whitetip sharks. Resolution 13/08 calls for a tran-sition to non-entangling FADs in purse seine fisheries start-ing in 2014. Sea Turtles. Resolution 12/04 (which supersedes various prior measures) requires IOTC members to mitigate sea turtle mortality and to provide data on turtle bycatch to the SC. The measure has specific requirements for longline and purse seine operators to facilitate the appropriate handling and release of live turtles. Resolution 13/08 calls for a transi-tion to non-entangling FADs in purse seine fisheries starting in 2014. Sea birds. Resolution 12/06 (which supersedes various prior measures) requires longliners operating south of 25°S to use at least two of several mitigation measures such as weighted branch lines or tori (bird-scaring) lines. The measure also requires IOTC members to provide data on interactions between fisheries and sea birds to the SC. Cetaceans. Resolution 13/02 prohibits deliberate purse seine sets around cetaceans and requires reporting of interactions. Other finfish. Resolution 15/05 requires IOTC members to make any possible effort to reduce the level of catches of striped marlin, black marlin and blue marlin in 2016. The baseline of the reduction of catches shall be the average catches for the period between 2009 and 2014. It also re-quires the release of specimens of those species if brought alive on board. Resolution Monitoring and mitigation research. Resolution 10/04 estab-lished a regional observer program that requires at least 5% coverage for vessels over 24 m, and for smaller vessels operating in the high seas. Resolution 08/04 requires long-liners greater than 24 m overall, as well as smaller longliners operating in the high seas, to have electronic logbooks and record and report data on target and non-target species to

the SC. Monitoring of bycatches in the gillnet fisheries is extremely poor. WCPFC Sea Turtles. CMM 2008-03 instructs WCPFC members to implement the FAO (2009) guidelines for reducing sea turtle mortality, and requires longline operators to use line cutters and de-hookers to handle and promptly release sea turtles caught or entangled. The measure also requires purse seine operators to avoid setting on turtles if possible and to disen-tangle/release them when caught alive. Sharks. CMM-2010-07 requires reporting of shark catches and discards by gear type and species. The measure also established a limit on the ratio of shark fins to total shark weight that can be retained onboard fishing vessels, and encourages the release of live sharks. CMM-2011-04 prohib-its the retention on board of oceanic white tip sharks and CMM-13-08 does the same for silky sharks. CMM-2012-04 prohibits deliberate purse seine sets around whale sharks and requires reporting of interactions. For longline fisheries that target tunas and billfishes, CMM-2014-05 requires Members to either not use wire trace as branch lines or not use shark lines; for fisheries targeting sharks, it requires a management plan to limit shark catches. WCPFC initiated a research plan aimed at improving statistics and observer coverage on sharks and conducting assessments for key shark species (Clarke and Harley, 2010). Sea birds. CMM 2012-07 requires longliners operating north of 23°N and south of 23°S to use at least two of several mitigation measures such as weighted branch lines or tori (bird-scaring) lines. The measure also encourages mitigation research to be conducted by WCPFC members. Cetaceans. CMM-2011-03 prohibits deliberate purse seine sets around cetaceans and requires reporting of interactions. Other finfish. Striped marlin are also caught as bycatch in longline fisheries; this species is of more concern because it has been declining in abundance. The WCPFC adopted CMM 2010-01 which sets a cap on the catch of striped marlin for each member relative to historical levels. Monitoring and mitigation research. With the exception of sharks under CMM 2009-04, reporting of bycatch species is not mandatory at WCPFC, so much of the information available comes from observer programs. The WCPFC has a Regional Observer Program that, since 2010, is intended to have 100% coverage on purse seine vessels that fish on the high seas or between two or more EEZs. As these data become available and are analyzed by the Scientific Commit-tee, monitoring should improve. National observer programs are also run by WCPFC members, but it is not clear that all of the bycatch information collected in those programs is made available to the SC for integrated analyses. For longline fisheries, observer coverage is poor overall. Much of the information available is from bilateral EEZ access agreements in Pacific Island countries. Observer coverage for distant-water fleets is extremely low.


A PPE ND I X 2 . VE RS I ON L OG DATE TE CH RE P . CH AN GES

11/2015 2015-03A

- Updated IATTC catch data, stock status and management - Updated WCPFC catch data - Updated Pacific-Wide catch data, stock status - Updated ICCAT catch data, stock status - Updated IOTC management - Changed Purse Seine - Dolphin-tuna association fishing method rating from Green to Yellow

02/2015 2015-03

- Updated WCPFC catch data and management - Updated ICCAT stock status and management - Updated IOTC stock status - Updated CCSBT stock status and management - Updated PBF management

08/2014 2014-09 - Updated IATTC stock status and management - Updated WCPFC stock status - Updated IOTC management - Updated Pacific-wide stock status

12/2013 2013-04B - Updated ICCAT stock status and management - Updated IOTC stock status - Updated WCPFC stock status and management - Updated CCSBT management

08/2013 2013-04A - Updated IATTC stock status - Updated Pacific bluefin - Updated IATTC management measures - Updated IOTC management measures

04/2013 2013-04 - Updated WCPFC catch data - Separated gillnet catches from "other" gears in the IO - Disaggregated Pacific-wide stocks - Added section on HCRs and Reference points for each stock

12/2012 2012-04B - Updated ICCAT stock status and management - Updated WCPFC stock status and management for tropical tunas - Updated Pacific-wide stock status - Updated CCSBT status and management - Updated general introduction - Modified life-history tables (K. Schaefer review)

07/2012 2012-04A - Updated EPO stock status - Updated WCPFC, IOTC and IATTC conservation measures adopted in 2012 - Corrected F status for North Pacific albacore - Updated Pacific bluefin catches

04/2012 2012-04 - Added 4 bluefin stocks - Reformatted entire report - Added Exec. Summary, Glossary and Introductory sections - Reorganized presentation of stocks to match regions

12/2011 2011-04C - Updated IO stock status to reflect 12/2011 IOTC SC meeting - Updated AO management to reflect 11/2011 ICCAT Comm. meeting


11/2011 2011-04B - Updated AO stock status to reflect 10/2011 ICCAT SCRS meeting - Updated WCPO stock status to reflect 08/2011 WCPFC SC meeting

08/2011 2011-04A - Updated EPO management to reflect 06/2011 IATTC Comm. Meeting Note: Doc header erroneously labeled "May" instead of "August"

05/2011 2011-04 - Updated EPO stock status to reflect 05/2011 IATTC SAC meeting - Added new rating factor Environment (bycatch) -Added more exhaustive information on RFMO resolutions

02/2011 -- - IOTC stock status update

10/2010 -- - ICCAT stock status update

09/2010 -- - WCPFC stock status update

09/2010 -- - IATTC stock status update

05/2010 -- - Updated entire report - Added color ratings for F and Biomass

05/2009 -- - First stock status report for 19 stocks

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